[1] Two elements which can form a large number of compounds are
A.
Carbon and Hydrogen
B.
Carbon and Nitrogen
C.
Carbon and Oxygen
D.
Carbon and Sulphur
Ans:
Carbon and Hydrogen
Explanation :
The carbon-hydrogen bond (C-H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. Compound classes consisting solely of C-H bonds and C-C bonds are alkanes, alkenes, alkynes, and aromatic hydrocarbons. Collectively they are known as hydrocarbons.
[2] An inert gas mixed with oxygen given to patients suffering from restricted breathing is –
A.
Helium
B.
Krypton
C.
Radon
D.
Argon
Ans:
Helium
Explanation :
Heliox is breathing has composed of a mixture of helium (He) and oxygen (O2). Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas
[3] Brass is an alloy of -
A.
Lead and tin
B.
Zine and copper
C.
Antimony, tin and lead
D.
Zinc, tin and copper
Ans:
Zine and copper
Explanation :
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin. Bronze does not necessarily contain tin, and a variety of alloys of copper, including alloys with arsenic, phosphorus, aluminium, manganese, and silicon, are commonly termed "brome".
[4] The chemical name of rat poison is -
A.
zinc oxide
B.
potassium cyanide
C.
lead nitrate
D.
zinc phosphide
Ans:
zinc phosphide
Explanation :
Zinc phosphide is used as a rodenticide. A mixture of food and zinc phosphide is left where the rodents can eat it. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas.
[5] Slag is a name given for -
A.
molten iron
B.
molten sand
C.
molten alumina
D.
molten calcium silicate
Ans:
molten alumina
Explanation :
Slag is a partially vitreous by-product of the process of smelting ore, which separates the desired metal fraction from the unwanted fraction. A good example is steelmaking slag: quicklime and magnetite are introduced for refractory protection, neutralizing the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
[6] Which one of the following statements is not correct? Vulcanisation of rubber makes it -
A.
soft and flexible
B.
strong and hard
C.
chemical resistant
D.
withstand higher temperatures
Ans:
soft and flexible
Explanation :
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.
[7] Stainless steel is an alloy of -
A.
chromium and carbon
B.
chromium, carbon and iron
C.
chromium and iron
D.
carbon and iron
Ans:
chromium, carbon and iron
Explanation :
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Stainless steel s defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel differs from carbon steel by the amount of chromium present.
[8] For generation of biogas, the materials commonly used are —
A.
Animal wastes
B.
Crop residues
C.
Aquatic plants
D.
Forest residues
Ans:
Animal wastes
Explanation :
Biogas typically refers to a gas produced by breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of bi o fuel. Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops.
[9] Which one of the following minerals is found in Monazite sand?
A.
Potassium
B.
Uranium
C.
Thorium
D.
Sodium
Ans:
Thorium
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
The carbon-hydrogen bond (C-H bond) is a bond between carbon and hydrogen atoms that can be found in many organic compounds. Compound classes consisting solely of C-H bonds and C-C bonds are alkanes, alkenes, alkynes, and aromatic hydrocarbons. Collectively they are known as hydrocarbons.
[2] An inert gas mixed with oxygen given to patients suffering from restricted breathing is –
A.
Helium
B.
Krypton
C.
Radon
D.
Argon
Ans:
Helium
Explanation :
Heliox is breathing has composed of a mixture of helium (He) and oxygen (O2). Heliox has been used medically since the 1930s, and although the medical community adopted it initially to alleviate symptoms of upper airway obstruction, its range of medical uses has since expanded greatly, mostly because of the low density of the gas
[3] Brass is an alloy of -
A.
Lead and tin
B.
Zine and copper
C.
Antimony, tin and lead
D.
Zinc, tin and copper
Ans:
Zine and copper
Explanation :
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin. Bronze does not necessarily contain tin, and a variety of alloys of copper, including alloys with arsenic, phosphorus, aluminium, manganese, and silicon, are commonly termed "brome".
[4] The chemical name of rat poison is -
A.
zinc oxide
B.
potassium cyanide
C.
lead nitrate
D.
zinc phosphide
Ans:
zinc phosphide
Explanation :
Zinc phosphide is used as a rodenticide. A mixture of food and zinc phosphide is left where the rodents can eat it. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas.
[5] Slag is a name given for -
A.
molten iron
B.
molten sand
C.
molten alumina
D.
molten calcium silicate
Ans:
molten alumina
Explanation :
Slag is a partially vitreous by-product of the process of smelting ore, which separates the desired metal fraction from the unwanted fraction. A good example is steelmaking slag: quicklime and magnetite are introduced for refractory protection, neutralizing the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
[6] Which one of the following statements is not correct? Vulcanisation of rubber makes it -
A.
soft and flexible
B.
strong and hard
C.
chemical resistant
D.
withstand higher temperatures
Ans:
soft and flexible
Explanation :
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.
[7] Stainless steel is an alloy of -
A.
chromium and carbon
B.
chromium, carbon and iron
C.
chromium and iron
D.
carbon and iron
Ans:
chromium, carbon and iron
Explanation :
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Stainless steel s defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel differs from carbon steel by the amount of chromium present.
[8] For generation of biogas, the materials commonly used are —
A.
Animal wastes
B.
Crop residues
C.
Aquatic plants
D.
Forest residues
Ans:
Animal wastes
Explanation :
Biogas typically refers to a gas produced by breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of bi o fuel. Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops.
[9] Which one of the following minerals is found in Monazite sand?
A.
Potassium
B.
Uranium
C.
Thorium
D.
Sodium
Ans:
Thorium
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin. Bronze does not necessarily contain tin, and a variety of alloys of copper, including alloys with arsenic, phosphorus, aluminium, manganese, and silicon, are commonly termed "brome".
[4] The chemical name of rat poison is -
A.
zinc oxide
B.
potassium cyanide
C.
lead nitrate
D.
zinc phosphide
Ans:
zinc phosphide
Explanation :
Zinc phosphide is used as a rodenticide. A mixture of food and zinc phosphide is left where the rodents can eat it. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas.
[5] Slag is a name given for -
A.
molten iron
B.
molten sand
C.
molten alumina
D.
molten calcium silicate
Ans:
molten alumina
Explanation :
Slag is a partially vitreous by-product of the process of smelting ore, which separates the desired metal fraction from the unwanted fraction. A good example is steelmaking slag: quicklime and magnetite are introduced for refractory protection, neutralizing the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
[6] Which one of the following statements is not correct? Vulcanisation of rubber makes it -
A.
soft and flexible
B.
strong and hard
C.
chemical resistant
D.
withstand higher temperatures
Ans:
soft and flexible
Explanation :
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.
[7] Stainless steel is an alloy of -
A.
chromium and carbon
B.
chromium, carbon and iron
C.
chromium and iron
D.
carbon and iron
Ans:
chromium, carbon and iron
Explanation :
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Stainless steel s defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel differs from carbon steel by the amount of chromium present.
[8] For generation of biogas, the materials commonly used are —
A.
Animal wastes
B.
Crop residues
C.
Aquatic plants
D.
Forest residues
Ans:
Animal wastes
Explanation :
Biogas typically refers to a gas produced by breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of bi o fuel. Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops.
[9] Which one of the following minerals is found in Monazite sand?
A.
Potassium
B.
Uranium
C.
Thorium
D.
Sodium
Ans:
Thorium
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Slag is a partially vitreous by-product of the process of smelting ore, which separates the desired metal fraction from the unwanted fraction. A good example is steelmaking slag: quicklime and magnetite are introduced for refractory protection, neutralizing the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorus from the steel.
[6] Which one of the following statements is not correct? Vulcanisation of rubber makes it -
A.
soft and flexible
B.
strong and hard
C.
chemical resistant
D.
withstand higher temperatures
Ans:
soft and flexible
Explanation :
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.
[7] Stainless steel is an alloy of -
A.
chromium and carbon
B.
chromium, carbon and iron
C.
chromium and iron
D.
carbon and iron
Ans:
chromium, carbon and iron
Explanation :
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Stainless steel s defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel differs from carbon steel by the amount of chromium present.
[8] For generation of biogas, the materials commonly used are —
A.
Animal wastes
B.
Crop residues
C.
Aquatic plants
D.
Forest residues
Ans:
Animal wastes
Explanation :
Biogas typically refers to a gas produced by breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of bi o fuel. Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops.
[9] Which one of the following minerals is found in Monazite sand?
A.
Potassium
B.
Uranium
C.
Thorium
D.
Sodium
Ans:
Thorium
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Stainless steel s defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass. Stainless steel differs from carbon steel by the amount of chromium present.
[8] For generation of biogas, the materials commonly used are —
A.
Animal wastes
B.
Crop residues
C.
Aquatic plants
D.
Forest residues
Ans:
Animal wastes
Explanation :
Biogas typically refers to a gas produced by breakdown of organic matter in the absence of oxygen. Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of bi o fuel. Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomass, manure, sewage, municipal waste, green waste, plant material, and crops.
[9] Which one of the following minerals is found in Monazite sand?
A.
Potassium
B.
Uranium
C.
Thorium
D.
Sodium
Ans:
Thorium
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral. Monazite is an important are for thorium, lanthanum, and cerium. It is often found in placer deposits. The deposits in India are particularly rich in monazite. It has a hardness of 5.0 to 5.5 and is relatively dense, about 4.6 to 5.7 g/ cm3.
[10] Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
A.
Sodium
B.
Neon
C.
Hydrogen
D.
Nitrogen
Ans:
Sodium
Explanation :
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure. Low-pressure sodium lamps are the most efficient electrical light sources, but their yellow light restricts applications to outdoor lighting such as street lamps. High-pressure sodium lamps have a broader spectrum of light but poorer colour rendering than other types. Because sodium vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observatories employ them.
[11] The tip of the match-stick contains –
A.
phosphorus pentoxide
B.
white phosphorus
C.
red phosphorus
D.
phosphorus trichloricle
Ans:
red phosphorus
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
A typical modern match is made of a small wooden stick or stiff paper. One end is coated with a material that can be ignited by frictional heat generated by striking the match against a suitable surface. Matches are usually sold in quantity; wooden ones are packaged in boxes, and paper matches are clustered in rows stapled into matchbooks. They are commonly sold by tobacconists and many other kinds of shops.
[12] Commercially, sodium bicarbonate is known as –
A.
Washing soda
B.
Baking soda
C.
Bleaching powder
D.
Soda ash
Ans:
Baking soda
Explanation :
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin salæratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage.
[13] Which gas does not form the part, of atmosphere?
A.
Nitrogen
B.
Helium
C.
Chlorine
D.
None of the above
Ans:
Chlorine
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variations). Air is the name given to the atmosphere used in breathing and photosynthesis.
[14] The reaction between an acid and a base to give a salt and water is known as a -
A.
Neutralisation reaction
B.
Reduction reaction
C.
Oxidation reaction
D.
Exothermic reaction
Ans:
Neutralisation reaction
Explanation :
The effect of a base is nullified by an acid and vice-versa. Example: Reaction of Sodium hydroxide with hydrochloric acid- NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)
[15] Which of the following elements is obtained from sea weeds?
A.
Argon
B.
Sulphur
C.
Vanadium
D.
Iodine
Ans:
Iodine
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Seaweed is rich in iodine, a trace element essential for healthy thyroid function and a healthy metabolism. Iodine is particularly vital for pregnant and lactating women. Seaweed also contains zinc and antioxidants, which help strengthen immunity.
[16] Which of the following gases is most toxic?
A.
Carbon dioxide
B.
Carbon monoxide
C.
Sulphur dioxide
D.
Chlorine
Ans:
Carbon monoxide
Explanation :
Carbon monoxide (CO) is a colourless, odorless, and tasteless gas that is slightly lighter than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground- level ozone. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic.
[17] Electron affinity of noble gases is -
A.
zero
B.
Low
C.
High
D.
Very high
Ans:
zero
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Most elements 'want' to have a complete electron shell with 8 electrons. Since the Noble Gases already have that 'perfect status' then they have an affinity of 0.
[18] Curd is sour due to presence of –
A.
Tartaric acid
B.
Lactic acid
C.
Acetic acid
D.
Oxalic acid
Ans:
Lactic acid
Explanation :
Curds are a dairy product obtained by curdling (coagulating) milk with rennet or an edible acidic substance such as lemon juice or vinegar, and then draining off the liquid portion. The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. The remaining liquid, which contains only whey proteins, is the whey.
[19] Tear gas is –
A.
Chloroprene
B.
Carbonyl chloride
C.
Nitrous oxide
D.
Bleaching powder
Ans:
Carbonyl chloride
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Tear gas, formally known as a lachrymatory agent or ladnymator (from lacrima meaning "tear" in Latin), is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness. Common lachrymators include OC, CS, CR, CN (phenacyl chloride), nonivarnide, bromoacetone, xylyl bromide and syn-propanethial-S-oxide (from onions). Tear gas works by irritating mucous membranes in the eyes, nose, mouth and lungs, and causes crying, sneezing, coughing, difficulty breathing, pain in the eyes, temporary blindness, etc. Lachrymators are thought to act by attacking sulphydryl functional groups in enzymes.
[20] Saccharin is made up of –
A.
Toluene
B.
Phenol
C.
Propane
D.
Butane
Ans:
Toluene
Explanation :
Saccharin can be produced in various ways. The original route by Remsen & Fahlberg starts with toluene. Saccharin is an artificial sweetener. The basic substance, benzoic sulfilimine, has effectively no food energy and is much sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products such as drinks, candies, cookies, medicines, and toothpaste.
[21] PVC is obtained by the polymerisation of –
A.
Propane
B.
Vinyl chloride
C.
Styrene
D.
Acetylene
Ans:
Vinyl chloride
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Polyvinyl chloride is produced by polymerization of the monomer vinyl chloride (17CM). Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is cheaper and stronger than more traditional alternatives such as copper or ductile iron.
[22] Which of the following gases is present under pressure in soft drinks?
A.
Oxygen
B.
Nitrogen
C.
Carbon dioxide
D.
Nitrous oxide
Ans:
Carbon dioxide
Explanation :
Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable was for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.
[23] The substance which does not expand on going from liquid state to solid state is –
A.
Water
B.
Cast-iron
C.
Aluminium
D.
Type metal
Ans:
Type metal
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.
[24] Isobars are lines joining places having equal –
A.
Rainfall
B.
Pressure
C.
Population
D.
Height above sea-level
Ans:
Pressure
Explanation :
An isobar is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict future weather patterns.
[25] Global warming is mainly due to accumulation of –
A.
Oxides of nitrogen
B.
Oxides of sulphur
C.
Carbon dioxide
D.
Carbon monoxide
Ans:
Carbon dioxide
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.
Explanation :
Global Warming refers to average increase in the earth's temperature due to increase in pollution which results in greenhouse effect which in turn leads to climate change. Global warming may lead to rise in the sea level due to melting of glaciers, shrinkage of forests, changes in the rainfall pattern and wide range of impacts on plants and humans. The greenhouse gases such as carbon dioxide accumulate into the atmosphere and trap heat that would normally exit into the outer space.