[1] Wood Spirit is which of the following?
A.
Ethyl Alcohol
B.
Propanol
C.
Methyl Alcohol
D.
Butanol
Ans:
Methyl Alcohol
Explanation :
Methanol is also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits. It acquired the name "wood alcohol" because it was once produced chiefly as a byproduct of the destructive distillation of wood. Modern methanol is produced in a catalytic industrial process directly from carbon monoxide, carbon dioxide, and hydrogen.
[2] Alum stops bleeding in minor cuts because of –
A.
solvation
B.
emulsion
C.
dialysis
D.
coagulation
Ans:
coagulation
Explanation :
Coagulation is the process by which blood forms clots. It is an important part of homeostasis, the cessation of blood loss from a damaged vessel, wherein a damaged blood vessel wall is covered by a platelet and fibrin-containing clot to stop bleeding and begin repair of the damaged vessel. Disorders of coagulation can lead to an increased risk of bleeding (hemorrhage) or obstructive clotting (thrombosis). Alum in block form (usually potassium alum) is used as a blood coagulant. Styptic pencils containing aluminium sulfate or potassium aluminium sulfate are used as astringents to prevent bleeding from small shaving cuts. For example, alum blocks are commonly sold in pharmacies in India.
[3] 'Plaster of Paris' is made by partial dehydration of –
A.
epsom salt
B.
gypsum salt
C.
blue vitriol
D.
green vitriol
Ans:
gypsum salt
Explanation :
Plaster is a building material used for coating walls and ceilings. Plaster starts as a dry powder similar to mortar or cement and like those materials it is mixed with water to form a paste which liberates heat and then hardens. Unlike mortar and cement, plaster remains quite soft after setting, and can be easily manipulated with metal tools or even sandpaper. These characteristics make plaster suitable for a finishing, rather than a load-bearing material.
[4] The purity of gold is expressed in carats. The purest form of gold is–
A.
24 carats
B.
99.6 carats
C.
91.6 carats
D.
22 carats
Ans:
24 carats
Explanation :
Gold is a dense, soft, shiny, malleable and ductile metal. Gold has a bright yellow colour and luster traditionally considered attractive, which it maintains without oxidizing in air or water. The metal therefore occurs often in free elemental (native) form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium. Pure gold is too soft for day-to-day monetary use and is typically hardened by alloying with copper, silver or other base metals. The gold content of alloys is measured in carats (k). Pure gold is designated as 24k.
[5] Petroleum consists of a mixture of –
A.
Carbohydrates
B.
Carbonates
C.
Hydrocarbons
D.
Carbides
Ans:
Hydrocarbons
Explanation :
Petroleum (petroleum, from Latin: 'petra' (rock) + Latin: oleum (oil) or crude oil is a naturally occurring flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compoun.ds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from petrol (or gasoline) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 88 million barrels each day.
[6] What is a mixture of potassium nitrate powdered charcoal and sulfur called?
A.
paint
B.
aluminum
C.
brass
D.
gun powder
Ans:
gun powder
Explanation :
Gunpowder, also known as the retronym black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur (S), charcoal (C), and potassium nitrate (saltpeter, KNO3). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer.
[7] What among following is used to produce artificial rain?
A.
Copper oxide
B.
carbon monoxide
C.
silver iodide
D.
silver nitrate
Ans:
silver iodide
Explanation :
Artificial process of making rain is done by precipitation, a process of condensation of water vapors in the air. This is done by using cloud seeding chemicals like potassium iodide, silver iodide, liquid propane or solid carbon dioxide (dry ice).
[8] The isotope used for the production of atomic energy is -
A.
U-235
B.
U-238
C.
U-234
D.
U-236
Ans:
U-235
Explanation :
U235 is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope U238 it is fissile, i.e., it can sustain fission chain reaction. It is the only fissile isotope that is a primordial nuclide or found in significant quantity in nature. If at least one neutron from U235 fission strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be critical, and the mass of U required to produce the critical condition is said to be a critical mass.
[9] Which of the following is not a nucleon?
A.
Proton
B.
Neutron
C.
Electron
D.
Positron
Ans:
Positron
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Methanol is also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits. It acquired the name "wood alcohol" because it was once produced chiefly as a byproduct of the destructive distillation of wood. Modern methanol is produced in a catalytic industrial process directly from carbon monoxide, carbon dioxide, and hydrogen.
[2] Alum stops bleeding in minor cuts because of –
A.
solvation
B.
emulsion
C.
dialysis
D.
coagulation
Ans:
coagulation
Explanation :
Coagulation is the process by which blood forms clots. It is an important part of homeostasis, the cessation of blood loss from a damaged vessel, wherein a damaged blood vessel wall is covered by a platelet and fibrin-containing clot to stop bleeding and begin repair of the damaged vessel. Disorders of coagulation can lead to an increased risk of bleeding (hemorrhage) or obstructive clotting (thrombosis). Alum in block form (usually potassium alum) is used as a blood coagulant. Styptic pencils containing aluminium sulfate or potassium aluminium sulfate are used as astringents to prevent bleeding from small shaving cuts. For example, alum blocks are commonly sold in pharmacies in India.
[3] 'Plaster of Paris' is made by partial dehydration of –
A.
epsom salt
B.
gypsum salt
C.
blue vitriol
D.
green vitriol
Ans:
gypsum salt
Explanation :
Plaster is a building material used for coating walls and ceilings. Plaster starts as a dry powder similar to mortar or cement and like those materials it is mixed with water to form a paste which liberates heat and then hardens. Unlike mortar and cement, plaster remains quite soft after setting, and can be easily manipulated with metal tools or even sandpaper. These characteristics make plaster suitable for a finishing, rather than a load-bearing material.
[4] The purity of gold is expressed in carats. The purest form of gold is–
A.
24 carats
B.
99.6 carats
C.
91.6 carats
D.
22 carats
Ans:
24 carats
Explanation :
Gold is a dense, soft, shiny, malleable and ductile metal. Gold has a bright yellow colour and luster traditionally considered attractive, which it maintains without oxidizing in air or water. The metal therefore occurs often in free elemental (native) form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium. Pure gold is too soft for day-to-day monetary use and is typically hardened by alloying with copper, silver or other base metals. The gold content of alloys is measured in carats (k). Pure gold is designated as 24k.
[5] Petroleum consists of a mixture of –
A.
Carbohydrates
B.
Carbonates
C.
Hydrocarbons
D.
Carbides
Ans:
Hydrocarbons
Explanation :
Petroleum (petroleum, from Latin: 'petra' (rock) + Latin: oleum (oil) or crude oil is a naturally occurring flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compoun.ds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from petrol (or gasoline) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 88 million barrels each day.
[6] What is a mixture of potassium nitrate powdered charcoal and sulfur called?
A.
paint
B.
aluminum
C.
brass
D.
gun powder
Ans:
gun powder
Explanation :
Gunpowder, also known as the retronym black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur (S), charcoal (C), and potassium nitrate (saltpeter, KNO3). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer.
[7] What among following is used to produce artificial rain?
A.
Copper oxide
B.
carbon monoxide
C.
silver iodide
D.
silver nitrate
Ans:
silver iodide
Explanation :
Artificial process of making rain is done by precipitation, a process of condensation of water vapors in the air. This is done by using cloud seeding chemicals like potassium iodide, silver iodide, liquid propane or solid carbon dioxide (dry ice).
[8] The isotope used for the production of atomic energy is -
A.
U-235
B.
U-238
C.
U-234
D.
U-236
Ans:
U-235
Explanation :
U235 is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope U238 it is fissile, i.e., it can sustain fission chain reaction. It is the only fissile isotope that is a primordial nuclide or found in significant quantity in nature. If at least one neutron from U235 fission strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be critical, and the mass of U required to produce the critical condition is said to be a critical mass.
[9] Which of the following is not a nucleon?
A.
Proton
B.
Neutron
C.
Electron
D.
Positron
Ans:
Positron
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Plaster is a building material used for coating walls and ceilings. Plaster starts as a dry powder similar to mortar or cement and like those materials it is mixed with water to form a paste which liberates heat and then hardens. Unlike mortar and cement, plaster remains quite soft after setting, and can be easily manipulated with metal tools or even sandpaper. These characteristics make plaster suitable for a finishing, rather than a load-bearing material.
[4] The purity of gold is expressed in carats. The purest form of gold is–
A.
24 carats
B.
99.6 carats
C.
91.6 carats
D.
22 carats
Ans:
24 carats
Explanation :
Gold is a dense, soft, shiny, malleable and ductile metal. Gold has a bright yellow colour and luster traditionally considered attractive, which it maintains without oxidizing in air or water. The metal therefore occurs often in free elemental (native) form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium. Pure gold is too soft for day-to-day monetary use and is typically hardened by alloying with copper, silver or other base metals. The gold content of alloys is measured in carats (k). Pure gold is designated as 24k.
[5] Petroleum consists of a mixture of –
A.
Carbohydrates
B.
Carbonates
C.
Hydrocarbons
D.
Carbides
Ans:
Hydrocarbons
Explanation :
Petroleum (petroleum, from Latin: 'petra' (rock) + Latin: oleum (oil) or crude oil is a naturally occurring flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compoun.ds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from petrol (or gasoline) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 88 million barrels each day.
[6] What is a mixture of potassium nitrate powdered charcoal and sulfur called?
A.
paint
B.
aluminum
C.
brass
D.
gun powder
Ans:
gun powder
Explanation :
Gunpowder, also known as the retronym black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur (S), charcoal (C), and potassium nitrate (saltpeter, KNO3). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer.
[7] What among following is used to produce artificial rain?
A.
Copper oxide
B.
carbon monoxide
C.
silver iodide
D.
silver nitrate
Ans:
silver iodide
Explanation :
Artificial process of making rain is done by precipitation, a process of condensation of water vapors in the air. This is done by using cloud seeding chemicals like potassium iodide, silver iodide, liquid propane or solid carbon dioxide (dry ice).
[8] The isotope used for the production of atomic energy is -
A.
U-235
B.
U-238
C.
U-234
D.
U-236
Ans:
U-235
Explanation :
U235 is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope U238 it is fissile, i.e., it can sustain fission chain reaction. It is the only fissile isotope that is a primordial nuclide or found in significant quantity in nature. If at least one neutron from U235 fission strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be critical, and the mass of U required to produce the critical condition is said to be a critical mass.
[9] Which of the following is not a nucleon?
A.
Proton
B.
Neutron
C.
Electron
D.
Positron
Ans:
Positron
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Petroleum (petroleum, from Latin: 'petra' (rock) + Latin: oleum (oil) or crude oil is a naturally occurring flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compoun.ds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from petrol (or gasoline) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 88 million barrels each day.
[6] What is a mixture of potassium nitrate powdered charcoal and sulfur called?
A.
paint
B.
aluminum
C.
brass
D.
gun powder
Ans:
gun powder
Explanation :
Gunpowder, also known as the retronym black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur (S), charcoal (C), and potassium nitrate (saltpeter, KNO3). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer.
[7] What among following is used to produce artificial rain?
A.
Copper oxide
B.
carbon monoxide
C.
silver iodide
D.
silver nitrate
Ans:
silver iodide
Explanation :
Artificial process of making rain is done by precipitation, a process of condensation of water vapors in the air. This is done by using cloud seeding chemicals like potassium iodide, silver iodide, liquid propane or solid carbon dioxide (dry ice).
[8] The isotope used for the production of atomic energy is -
A.
U-235
B.
U-238
C.
U-234
D.
U-236
Ans:
U-235
Explanation :
U235 is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope U238 it is fissile, i.e., it can sustain fission chain reaction. It is the only fissile isotope that is a primordial nuclide or found in significant quantity in nature. If at least one neutron from U235 fission strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be critical, and the mass of U required to produce the critical condition is said to be a critical mass.
[9] Which of the following is not a nucleon?
A.
Proton
B.
Neutron
C.
Electron
D.
Positron
Ans:
Positron
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Artificial process of making rain is done by precipitation, a process of condensation of water vapors in the air. This is done by using cloud seeding chemicals like potassium iodide, silver iodide, liquid propane or solid carbon dioxide (dry ice).
[8] The isotope used for the production of atomic energy is -
A.
U-235
B.
U-238
C.
U-234
D.
U-236
Ans:
U-235
Explanation :
U235 is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope U238 it is fissile, i.e., it can sustain fission chain reaction. It is the only fissile isotope that is a primordial nuclide or found in significant quantity in nature. If at least one neutron from U235 fission strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be critical, and the mass of U required to produce the critical condition is said to be a critical mass.
[9] Which of the following is not a nucleon?
A.
Proton
B.
Neutron
C.
Electron
D.
Positron
Ans:
Positron
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Nucleon is one of the particles that makes up the atomic nucleus. Each atomic nucleus consists of one or more nucleons, and each atom in turn consists of a cluster of nucleons surrounded by one or more electrons. There are two kinds of nucleon: the neutron and the proton. The mass number of a given atomic isotope is identical to its number of nucleons. Thus the term nucleon number may be used in place of the more common terms mass number or atomic mass number.
[10] Which of the metallic ions is essential for blood clotting?
A.
Na+
B.
Ca++
C.
K+
D.
Fe++
Ans:
Ca++
Explanation :
Calcium ions along with vitamin K are essential for clotting process as all the reaction in the clotting process take place in the presence of calcium ions. It is very important for the conversion reaction of prothrombin into the thrombin.
[11] CuO + H2 = Cu + H2O. This equation is an example of -
A.
Oxidation
B.
Decomposition
C.
Reduction
D.
Redox
Ans:
Redox
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species. In redox reaction the oxidation number of a molecule, atom, or ion changes by gaining or losing an electron. In the reaction : CuO+H2⟶Cu+H2O n the reaction H2 is oxidized since it has lost electrons and Cu is reduced since it has gained electrons.
[12] The gas that is used in the manufacture of vanaspati ghee is -
A.
Oxygen
B.
Carbon dioxide
C.
Hydrogen
D.
Nitrogen
Ans:
Hydrogen
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. The largest scale application of hydrogenation is for the processing of vegetableoils (fats to give margarine and related spreads and shortenings).
[13] The anode of a dry cell is made up of -
A.
Iron
B.
Cadmium
C.
Zine
D.
Lead
Ans:
Zine
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half- reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
[14] The chemical used in enabalining biological materials is –
A.
formaldehyde in water
B.
formaldehyde in methanol
C.
ethylene glycol
D.
gaseous formaldehyde
Ans:
formaldehyde in water
Explanation :
Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. Modern formaldehyde based embalming fluids are much kinder to the environment than those used in previous years.
[15] Which of the following is a mono-atomic gas?
A.
Oxygen
B.
Neon
C.
Nitrogen
D.
Fluorine
Ans:
Neon
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
All elements will be monatomic in the gas phase at sufficiently high temperatures. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. Monatomic hydrogen comprises about 75% of the elemental mass of the universe.
[16] What particles move around the nucleus of an atom and are negatively charged?
A.
Electrons
B.
Protons
C.
Positrons
D.
Neutrons
Ans:
Electrons
Explanation :
Circling around outside the nucleus are tiny little particles called electrons. Electrons have a negative charge. Electrons spin as they circle the nucleus billions of times every second. They are arranged in energy levels around the nucleus. When electrons gain or lose energy, they jump between energy levels as they are rotating around the nucleus.
[17] Among the following, which is always found in free-state in nature?
A.
Gold
B.
Silver
C.
Sodium
D.
Copper
Ans:
Gold
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Gold is the least reactive in the reactivity series. Since it does not react with other elements, it is found in a free form. Only gold, silver, copper and the platinum metals occur in nature in larger amounts. Non- metallic elements occurring in the native state include carbon and sulfur.
[18] The Fungus which is used in the alcohol industry is –
A.
Mushroom
B.
Candida Aibicans
C.
Yeast
D.
Rhizopus
Ans:
Yeast
Explanation :
Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols — for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages.
[19] Gold dissolves in –
A.
Hydrochloric acid
B.
Nitric acid
C.
Aqua-regia
D.
Acetic acid
Ans:
Aqua-regia
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.
[20] Rock salt is a mineral containing –
A.
potassium
B.
magnesium
C.
sodium
D.
iron
Ans:
sodium
Explanation :
Halite, commonly known as rock salt, is the mineral form of sodium chloride (NaCl). Halite forms isometric crystals. It commonly occurs with other evaporite deposit minerals such as several of the sulfates, halides, and borates.
[21] In a nuclear reactor the material use for absorbing neutrons is –
A.
zinc
B.
radium
C.
lead
D.
cadmium
Ans:
cadmium
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
One isotope of cadmium, 113Cd, absorbs neutrons with very high probability if they have an energy below the cadmium cut-off and transmits them otherwise. The cadmium cut-off is about 0.5 eV. Neutrons with energy below the cut-off are deemed slow neutrons, distinguishing them from intermediate and fast neutrons.
[22] Solder metal is an alloy of –
A.
lead and tin
B.
lead and antimony
C.
copper and zinc
D.
copper and tin
Ans:
lead and tin
Explanation :
A solder is a fusible metal alloy of tin and lead with a melting point or melting range of 90 to 450°C, used in a process called soldering where it is melted to jain metallic surfaces. It is especially useful in electronics and plumbing.
[23] Ozone depletion in the atmosphere is mainly caused by -
A.
sulphur dioxide
B.
nitrogen dioxide
C.
hydrogen sulphide
D.
chlorofluorocarbon
Ans:
chlorofluorocarbon
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, hydrogen and fluorine, produced as a volatile derivative of methane and ethane. They contribute to ozone depletion in the upper atmosphere.
[24] All noble gases are -
A.
Colourless
B.
Odourless
C.
Colourless and Odourless
D.
Light blue
Ans:
Colourless and Odourless
Explanation :
Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.
[25] Which halide is used in making sensitive emulsion on photographic film?
A.
Sodium chloride
B.
Silver bromide
C.
Silver iodide
D.
Silver chloride
Ans:
Silver bromide
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
Explanation :
Silver bromide, a soft, pale-yellow, water insoluble salt well known for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.