[1] The most abundant metal in the Earth’s crust is -
A.
zinc
B.
copper
C.
aluminium
D.
iron
Ans:
aluminium
Explanation :
The most abundant metal on Earth is aluminum. Aluminum is the third most abundant element in the Earth's crust, and makes up 8 percent of it by parts per million. The most abundant element in the Earth's crust is Oxygen followed by Silicon. Both of these are non-metals.
[2] Adding Cl2 to benzene in the presence of AlCl3 is an example of –
A.
Elimination reaction
B.
Substitution reaction
C.
None of the options
D.
Addition reaction
Ans:
Substitution reaction
Explanation :
The reaction between benzene and chlorine in the presence of a catalyst such as aluminium chloride gives Chlorobenzene. This reaction is an example of electrophilic substitution reaction since one of the hydrogen atoms on the ring is replaced by a chlorine atom.
[3] Freon is used as -
A.
Oxidant
B.
Refrigerant
C.
Catalyst
D.
Both (1) and (2)
Ans:
Refrigerant
Explanation :
Freon uses for a number of halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have typically been used as refrigerants and as aerosol propellants.
[4] Nitrification is the biological process of converting –
A.
N9 into nitrate
B.
N2 into nitrite
C.
Ammonia into nitrite
D.
Ammonia into N2
Ans:
Ammonia into nitrite
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil.
[5] The most pure form of Carbon among the options is –
A.
Anthracite
B.
Lampblack
C.
Graphite
D.
Wood Charcoal
Ans:
Anthracite
Explanation :
There are three forms of pure carbon: graphite, coal and diamond. Among coal, Anthracite has the highest carbon content, the fewest impurities, and the highest calorific content of all types of coal except for graphite. Anthracite is the most metamorphosed type of coal in which the carbon content is between 92.1% and 98%.
[6] Chemical properties of isotopes –
A.
must be same
B.
must be different
C.
need not be same
D.
need not be different
Ans:
must be same
Explanation :
Isotopes of an element have similar chemical properties as they have the same number of electrons as an atom of that element. The electron arrangement is the same owing to same chemical properties. However, they have different numbers of neutrons, which
[7] Sour taste of lemon is due to the presence of which of the follow-ing?
A.
Citric acid
B.
Acetic acid
C.
Oxalic acid
D.
Formic acid
Ans:
Citric acid
Explanation :
Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3. Citric acid is found in many fruits but lemon contains large quantity of citric acid. The distinctive sour taste of lemon juice makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie.
[8] Ethylene is a molecule.
A.
polar
B.
ionic
C.
covalent
D.
nonpolar
Ans:
nonpolar
Explanation :
Ethylene (C2H4) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electro negativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.
[9] If water smells bad, then that odour can be removed by adding –
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
The most abundant metal on Earth is aluminum. Aluminum is the third most abundant element in the Earth's crust, and makes up 8 percent of it by parts per million. The most abundant element in the Earth's crust is Oxygen followed by Silicon. Both of these are non-metals.
[2] Adding Cl2 to benzene in the presence of AlCl3 is an example of –
A.
Elimination reaction
B.
Substitution reaction
C.
None of the options
D.
Addition reaction
Ans:
Substitution reaction
Explanation :
The reaction between benzene and chlorine in the presence of a catalyst such as aluminium chloride gives Chlorobenzene. This reaction is an example of electrophilic substitution reaction since one of the hydrogen atoms on the ring is replaced by a chlorine atom.
[3] Freon is used as -
A.
Oxidant
B.
Refrigerant
C.
Catalyst
D.
Both (1) and (2)
Ans:
Refrigerant
Explanation :
Freon uses for a number of halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have typically been used as refrigerants and as aerosol propellants.
[4] Nitrification is the biological process of converting –
A.
N9 into nitrate
B.
N2 into nitrite
C.
Ammonia into nitrite
D.
Ammonia into N2
Ans:
Ammonia into nitrite
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil.
[5] The most pure form of Carbon among the options is –
A.
Anthracite
B.
Lampblack
C.
Graphite
D.
Wood Charcoal
Ans:
Anthracite
Explanation :
There are three forms of pure carbon: graphite, coal and diamond. Among coal, Anthracite has the highest carbon content, the fewest impurities, and the highest calorific content of all types of coal except for graphite. Anthracite is the most metamorphosed type of coal in which the carbon content is between 92.1% and 98%.
[6] Chemical properties of isotopes –
A.
must be same
B.
must be different
C.
need not be same
D.
need not be different
Ans:
must be same
Explanation :
Isotopes of an element have similar chemical properties as they have the same number of electrons as an atom of that element. The electron arrangement is the same owing to same chemical properties. However, they have different numbers of neutrons, which
[7] Sour taste of lemon is due to the presence of which of the follow-ing?
A.
Citric acid
B.
Acetic acid
C.
Oxalic acid
D.
Formic acid
Ans:
Citric acid
Explanation :
Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3. Citric acid is found in many fruits but lemon contains large quantity of citric acid. The distinctive sour taste of lemon juice makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie.
[8] Ethylene is a molecule.
A.
polar
B.
ionic
C.
covalent
D.
nonpolar
Ans:
nonpolar
Explanation :
Ethylene (C2H4) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electro negativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.
[9] If water smells bad, then that odour can be removed by adding –
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Freon uses for a number of halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have typically been used as refrigerants and as aerosol propellants.
[4] Nitrification is the biological process of converting –
A.
N9 into nitrate
B.
N2 into nitrite
C.
Ammonia into nitrite
D.
Ammonia into N2
Ans:
Ammonia into nitrite
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil.
[5] The most pure form of Carbon among the options is –
A.
Anthracite
B.
Lampblack
C.
Graphite
D.
Wood Charcoal
Ans:
Anthracite
Explanation :
There are three forms of pure carbon: graphite, coal and diamond. Among coal, Anthracite has the highest carbon content, the fewest impurities, and the highest calorific content of all types of coal except for graphite. Anthracite is the most metamorphosed type of coal in which the carbon content is between 92.1% and 98%.
[6] Chemical properties of isotopes –
A.
must be same
B.
must be different
C.
need not be same
D.
need not be different
Ans:
must be same
Explanation :
Isotopes of an element have similar chemical properties as they have the same number of electrons as an atom of that element. The electron arrangement is the same owing to same chemical properties. However, they have different numbers of neutrons, which
[7] Sour taste of lemon is due to the presence of which of the follow-ing?
A.
Citric acid
B.
Acetic acid
C.
Oxalic acid
D.
Formic acid
Ans:
Citric acid
Explanation :
Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3. Citric acid is found in many fruits but lemon contains large quantity of citric acid. The distinctive sour taste of lemon juice makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie.
[8] Ethylene is a molecule.
A.
polar
B.
ionic
C.
covalent
D.
nonpolar
Ans:
nonpolar
Explanation :
Ethylene (C2H4) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electro negativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.
[9] If water smells bad, then that odour can be removed by adding –
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
There are three forms of pure carbon: graphite, coal and diamond. Among coal, Anthracite has the highest carbon content, the fewest impurities, and the highest calorific content of all types of coal except for graphite. Anthracite is the most metamorphosed type of coal in which the carbon content is between 92.1% and 98%.
[6] Chemical properties of isotopes –
A.
must be same
B.
must be different
C.
need not be same
D.
need not be different
Ans:
must be same
Explanation :
Isotopes of an element have similar chemical properties as they have the same number of electrons as an atom of that element. The electron arrangement is the same owing to same chemical properties. However, they have different numbers of neutrons, which
[7] Sour taste of lemon is due to the presence of which of the follow-ing?
A.
Citric acid
B.
Acetic acid
C.
Oxalic acid
D.
Formic acid
Ans:
Citric acid
Explanation :
Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3. Citric acid is found in many fruits but lemon contains large quantity of citric acid. The distinctive sour taste of lemon juice makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie.
[8] Ethylene is a molecule.
A.
polar
B.
ionic
C.
covalent
D.
nonpolar
Ans:
nonpolar
Explanation :
Ethylene (C2H4) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electro negativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.
[9] If water smells bad, then that odour can be removed by adding –
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3. Citric acid is found in many fruits but lemon contains large quantity of citric acid. The distinctive sour taste of lemon juice makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie.
[8] Ethylene is a molecule.
A.
polar
B.
ionic
C.
covalent
D.
nonpolar
Ans:
nonpolar
Explanation :
Ethylene (C2H4) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electro negativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.
[9] If water smells bad, then that odour can be removed by adding –
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called "Adsorption", which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.
[10] The basic process taking place in nuclear reactors is -
A.
Radioactivity
B.
Fission
C.
Fusion
D.
None of the above
Ans:
Fission
Explanation :
A nuclear reactor produces and controls the release of energy from splitting the atoms of uranium, known as nuclear fission. When a fissile atomic nucleus such as uranium-235 or plutonium-239 absorbs a neutron, it undergoes nuclear fission in which the heavy nucleus splits into two or more lighter nuclei. The fission process produces free neutrons and gamma pho-tons, and releases a very large amount of energy.
[11] Malathion is a/an -
A.
insecticide
B.
fumigant
C.
preservative
D.
pesticide
Ans:
insecticide
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Malathion is an organophosphate (OP) insecticide that has been registered for use in the United States since 1956. It is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. It is of relatively low human toxicity.
[12] Glycol is used to manufacture which of the following?
A.
Nylon
B.
Artificial silk
C.
Terylene
D.
Rubber
Ans:
Terylene
Explanation :
Monoethylene glycol (MEG), also known as ethylene glycol (EG) or simply glycol, is a diol mostly used for the production of polyester fibers and polyethylene terephthalate (PET) resins. Polyethylene terephthalate is used to produce textiles, large soft-drink containers, photographic film, and overhead transparencies.
[13] During fermentation of sugar, the compound which is always formed is –
A.
Methyl Alcohol
B.
Ethyl Alcohol
C.
Acetic Acid
D.
Ethylene
Ans:
Ethyl Alcohol
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Fermentation is the conversion of sugar into car-bon dioxide has (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
[14] Warming Ammonium chloride with sodium hydrochloride in a test tube is an example of –
A.
Open system
B.
Closed system
C.
Isobaric system
D.
Isothermal system
Ans:
Open system
Explanation :
When heated, ammonlinm chloride decomposes into ammonia and hydrogen chloride. The thermal decomposition of ammonium chloride is a reversible chemical change. On heating above 340°C, it decomposes to form two gases such as ammonia and hydrogen chloride. On cooling, the reaction is reversed and solid ammonium chloride is formed.
[15] Laughing gas is –
A.
Nitric oxide
B.
Nitrous oxide
C.
Nitrogen trioxide
D.
Nitrogen pentoxide
Ans:
Nitrous oxide
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Nitrous oxide, commonly known as laughing gas or nitrous, is a chemical compound, an oxide of nitrogen with the formula N ₂O. At room temperature, it is a colourless non-flammable gas, with a slight metallic scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
[16] Calcium salts used as fertilizer is –
A.
Calcium Carbide
B.
Calcium Carbonate
C.
Calcium Cyanide
D.
Calcium Sulphate
Ans:
Calcium Sulphate
Explanation :
Sulphur (as sulphate) is a major plant nutrient, and is essential for crop growth. Calcium Sulphate (gypsum) is used to improve soil quality. Calcium sulphate acts as a pH buffer, which can contribute to neutralizing both soil alkalinity and acidity. It is mainly used for the reclamation of sodic soils through ion exchange (calcium replacing sodium).
[17] Which one of the following has a maximum tendency to form M^3 ion?
A.
N
B.
Bi
C.
P
D.
As
Ans:
N
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
The general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitro- gen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble has configuration, forming nitride N3- ions.
[18] Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
C.
CuSO4
D.
Cu(NO3)2
Ans:
CuCO3 Cu(OH)2
Explanation :
When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.
[19] Bagasse, a byproduct of sugar manufacturing industry, is used for the production of -
A.
Glass
B.
Paper
C.
Rubber
D.
Cement
Ans:
Paper
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
0
[20] Bleaching powder is made from -
A.
Sulphur dioxide and gypsum
B.
Chlorine and Charcoal
C.
Soda ash and lime
D.
Lime and Chlorine
Ans:
Lime and Chlorine
Explanation :
The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.
[21] Which one of the following does not contain silver?
A.
Horn silver
B.
Ruby silver
C.
German silver
D.
Lunar caustic
Ans:
German silver
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.
[22] An important green-house gas other than methane being produced from the agricultural fields is–
A.
Nitrous oxide
B.
Ammonia
C.
Sulphur dioxide
D.
Arsine
Ans:
Nitrous oxide
Explanation :
Nitrous oxide (N2O) and methane (CH4) are the two major greenhouse gasses (GHG) emitted by agricultural activities. N2O accounts for around 8% of the warming impact of current human GHG emissions.
[23] Which one of the following contains maximum percentage of carbon?
A.
Cast iron
B.
Stainless steel
C.
Wrought iron
D.
High speed steel
Ans:
Cast iron
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.
[24] Which of the following appeared to be with a significant potential for accumulation through food chains?
A.
DDT
B.
Parathion
C.
Lindane
D.
Carbary
Ans:
DDT
Explanation :
Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.
[25] The moderator used in a nuclear reactor is –
A.
Uranium
B.
Radium
C.
Ordinary water
D.
Graphite
Ans:
Ordinary water
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.
Explanation :
Light water (ordinary water) is used as the moderator in U.S. reactors as well as the cooling agent. It acts as the means by which heat is removed to produce steam for turning the turbines of the electric generators.