[1] Milk is a colloidal system in which:
A.
Water is dispersed in fat
B.
Fat is dispersed in water
C.
Fat and water are dispersed in each other
D.
Fat is dissolved
Ans:
Fat is dispersed in water
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.
[2] The presence of ozone in the stratosphere is responsible for –
A.
increasing the average global temperature in recent years
B.
higher rate of photosynthesis
C.
checking the penetration of ultra-violet rays to the earth
D.
supplying oxygen for people travelling in jets
Ans:
checking the penetration of ultra-violet rays to the earth
Explanation :
Ozone in the ozone layer filters out sunlight wavelengths from about 200 nm UV rays to 315 nm, with ozone peak absorption at about 250 nm. This ozone UV absorption is important to life, since it extends the absorption of UV by ordinary oxygen and nitrogen in air (which absorbs all wavelengths < 200 nm) through the lower UV-C (200 nm-280 nm) and the entire UV-B band (280 nm-315 nm).
[3] The advantage of detergents over soaps is –
A.
Detergents are soluble in water
B.
Detergents could not give much lather
C.
Detergents give lather even with hard water
D.
Soaps give lather with only soft water
Ans:
Detergents give lather even with hard water
Explanation :
Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
[4] What is the objective of the 'Kyoto Protocol'?
A.
To abolish child labour
B.
To eliminate nuclear weapons
C.
To increase ground water levels
D.
To reduce greenhouse gases
Ans:
To reduce greenhouse gases
Explanation :
The Kyoto Protocol is an international treaty which extends the 19992 United Nations Framework Convention on Climate Change (UNFCCC) that commits State Parties to reduce green hourse gas emissions.
[5] The lustre of the metals is because of –
A.
high density, due to closed packing of atoms
B.
high polish
C.
reflection of light due to the presence of free electrons
D.
absorption of light due to the presence of cavities
Ans:
reflection of light due to the presence of free electrons
Explanation :
Lustre (or luster) is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the latin lux, meaning "light", and generally implies radiance, gloss, or brilliance. Metals in general have high electrical conductivity, high thermal conductivity, and high density. Typically they are malleable and ductile, deforming -under stress without cleaving.
[6] Cloud is a colloidal dispersion of –
A.
Air in a dispersion medium of water
B.
Fog in a dispersion medium of water
C.
Mist in a dispersion medium of air
D.
Water drops in a dispersion medium of air
Ans:
Water drops in a dispersion medium of air
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.
[7] Conduction band electrons have more mobility than holes because they –
A.
are lighter
B.
experience collision less frequently
C.
have negative charge
D.
need less energy to move them
Ans:
experience collision less frequently
Explanation :
When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same. Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted due to collisions. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.
[8] Carbon dioxide is called a greenhouse gas because -
A.
its concentration remains always higher than other gases
B.
it is used in photosynthesis
C.
it absorbs infrared radiation
D.
it emits visible radiation
Ans:
it absorbs infrared radiation
Explanation :
There are certain gases in the atmosphere of the earth which can trap heat. These gases are called the greenhouse gases, The common gases are carbon dioxide, methane, nitrous oxide, ozone and water vapour. These gases are able to capture and trap the heat in the atmosphere. The heat is in the form of infrared radiation. This entrapment of the infrared radiations causes rise in the temperature in the earth's atmosphere.
[9] Sullage water is –
A.
waste water released from kitchen
B.
waste water released from toilets
C.
waste water released from factories
D.
waste water released from hospitals
Ans:
waste water released from kitchen
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.
[2] The presence of ozone in the stratosphere is responsible for –
A.
increasing the average global temperature in recent years
B.
higher rate of photosynthesis
C.
checking the penetration of ultra-violet rays to the earth
D.
supplying oxygen for people travelling in jets
Ans:
checking the penetration of ultra-violet rays to the earth
Explanation :
Ozone in the ozone layer filters out sunlight wavelengths from about 200 nm UV rays to 315 nm, with ozone peak absorption at about 250 nm. This ozone UV absorption is important to life, since it extends the absorption of UV by ordinary oxygen and nitrogen in air (which absorbs all wavelengths < 200 nm) through the lower UV-C (200 nm-280 nm) and the entire UV-B band (280 nm-315 nm).
[3] The advantage of detergents over soaps is –
A.
Detergents are soluble in water
B.
Detergents could not give much lather
C.
Detergents give lather even with hard water
D.
Soaps give lather with only soft water
Ans:
Detergents give lather even with hard water
Explanation :
Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
[4] What is the objective of the 'Kyoto Protocol'?
A.
To abolish child labour
B.
To eliminate nuclear weapons
C.
To increase ground water levels
D.
To reduce greenhouse gases
Ans:
To reduce greenhouse gases
Explanation :
The Kyoto Protocol is an international treaty which extends the 19992 United Nations Framework Convention on Climate Change (UNFCCC) that commits State Parties to reduce green hourse gas emissions.
[5] The lustre of the metals is because of –
A.
high density, due to closed packing of atoms
B.
high polish
C.
reflection of light due to the presence of free electrons
D.
absorption of light due to the presence of cavities
Ans:
reflection of light due to the presence of free electrons
Explanation :
Lustre (or luster) is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the latin lux, meaning "light", and generally implies radiance, gloss, or brilliance. Metals in general have high electrical conductivity, high thermal conductivity, and high density. Typically they are malleable and ductile, deforming -under stress without cleaving.
[6] Cloud is a colloidal dispersion of –
A.
Air in a dispersion medium of water
B.
Fog in a dispersion medium of water
C.
Mist in a dispersion medium of air
D.
Water drops in a dispersion medium of air
Ans:
Water drops in a dispersion medium of air
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.
[7] Conduction band electrons have more mobility than holes because they –
A.
are lighter
B.
experience collision less frequently
C.
have negative charge
D.
need less energy to move them
Ans:
experience collision less frequently
Explanation :
When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same. Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted due to collisions. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.
[8] Carbon dioxide is called a greenhouse gas because -
A.
its concentration remains always higher than other gases
B.
it is used in photosynthesis
C.
it absorbs infrared radiation
D.
it emits visible radiation
Ans:
it absorbs infrared radiation
Explanation :
There are certain gases in the atmosphere of the earth which can trap heat. These gases are called the greenhouse gases, The common gases are carbon dioxide, methane, nitrous oxide, ozone and water vapour. These gases are able to capture and trap the heat in the atmosphere. The heat is in the form of infrared radiation. This entrapment of the infrared radiations causes rise in the temperature in the earth's atmosphere.
[9] Sullage water is –
A.
waste water released from kitchen
B.
waste water released from toilets
C.
waste water released from factories
D.
waste water released from hospitals
Ans:
waste water released from kitchen
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.
[4] What is the objective of the 'Kyoto Protocol'?
A.
To abolish child labour
B.
To eliminate nuclear weapons
C.
To increase ground water levels
D.
To reduce greenhouse gases
Ans:
To reduce greenhouse gases
Explanation :
The Kyoto Protocol is an international treaty which extends the 19992 United Nations Framework Convention on Climate Change (UNFCCC) that commits State Parties to reduce green hourse gas emissions.
[5] The lustre of the metals is because of –
A.
high density, due to closed packing of atoms
B.
high polish
C.
reflection of light due to the presence of free electrons
D.
absorption of light due to the presence of cavities
Ans:
reflection of light due to the presence of free electrons
Explanation :
Lustre (or luster) is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the latin lux, meaning "light", and generally implies radiance, gloss, or brilliance. Metals in general have high electrical conductivity, high thermal conductivity, and high density. Typically they are malleable and ductile, deforming -under stress without cleaving.
[6] Cloud is a colloidal dispersion of –
A.
Air in a dispersion medium of water
B.
Fog in a dispersion medium of water
C.
Mist in a dispersion medium of air
D.
Water drops in a dispersion medium of air
Ans:
Water drops in a dispersion medium of air
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.
[7] Conduction band electrons have more mobility than holes because they –
A.
are lighter
B.
experience collision less frequently
C.
have negative charge
D.
need less energy to move them
Ans:
experience collision less frequently
Explanation :
When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same. Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted due to collisions. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.
[8] Carbon dioxide is called a greenhouse gas because -
A.
its concentration remains always higher than other gases
B.
it is used in photosynthesis
C.
it absorbs infrared radiation
D.
it emits visible radiation
Ans:
it absorbs infrared radiation
Explanation :
There are certain gases in the atmosphere of the earth which can trap heat. These gases are called the greenhouse gases, The common gases are carbon dioxide, methane, nitrous oxide, ozone and water vapour. These gases are able to capture and trap the heat in the atmosphere. The heat is in the form of infrared radiation. This entrapment of the infrared radiations causes rise in the temperature in the earth's atmosphere.
[9] Sullage water is –
A.
waste water released from kitchen
B.
waste water released from toilets
C.
waste water released from factories
D.
waste water released from hospitals
Ans:
waste water released from kitchen
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Lustre (or luster) is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the latin lux, meaning "light", and generally implies radiance, gloss, or brilliance. Metals in general have high electrical conductivity, high thermal conductivity, and high density. Typically they are malleable and ductile, deforming -under stress without cleaving.
[6] Cloud is a colloidal dispersion of –
A.
Air in a dispersion medium of water
B.
Fog in a dispersion medium of water
C.
Mist in a dispersion medium of air
D.
Water drops in a dispersion medium of air
Ans:
Water drops in a dispersion medium of air
Explanation :
A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.
[7] Conduction band electrons have more mobility than holes because they –
A.
are lighter
B.
experience collision less frequently
C.
have negative charge
D.
need less energy to move them
Ans:
experience collision less frequently
Explanation :
When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same. Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted due to collisions. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.
[8] Carbon dioxide is called a greenhouse gas because -
A.
its concentration remains always higher than other gases
B.
it is used in photosynthesis
C.
it absorbs infrared radiation
D.
it emits visible radiation
Ans:
it absorbs infrared radiation
Explanation :
There are certain gases in the atmosphere of the earth which can trap heat. These gases are called the greenhouse gases, The common gases are carbon dioxide, methane, nitrous oxide, ozone and water vapour. These gases are able to capture and trap the heat in the atmosphere. The heat is in the form of infrared radiation. This entrapment of the infrared radiations causes rise in the temperature in the earth's atmosphere.
[9] Sullage water is –
A.
waste water released from kitchen
B.
waste water released from toilets
C.
waste water released from factories
D.
waste water released from hospitals
Ans:
waste water released from kitchen
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same. Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted due to collisions. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.
[8] Carbon dioxide is called a greenhouse gas because -
A.
its concentration remains always higher than other gases
B.
it is used in photosynthesis
C.
it absorbs infrared radiation
D.
it emits visible radiation
Ans:
it absorbs infrared radiation
Explanation :
There are certain gases in the atmosphere of the earth which can trap heat. These gases are called the greenhouse gases, The common gases are carbon dioxide, methane, nitrous oxide, ozone and water vapour. These gases are able to capture and trap the heat in the atmosphere. The heat is in the form of infrared radiation. This entrapment of the infrared radiations causes rise in the temperature in the earth's atmosphere.
[9] Sullage water is –
A.
waste water released from kitchen
B.
waste water released from toilets
C.
waste water released from factories
D.
waste water released from hospitals
Ans:
waste water released from kitchen
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Sullage is a term used to descibe wastewater that wises as a byproduct of daily human activities such as showering, washing kitchen utensils, and doing the laundry. It is used water that does not contain excreta. Sullage is commonly referred to as gray water that is a mixture of water, soap, detergent, bleach, dirt, and other compounds discarded after use.
[10] A solution is -
A.
a homogeneous mixture of two or more substances
B.
a solid dissolved in a liquid
C.
a solid dissolved i water
D.
a mixture of two liquids
Ans:
a homogeneous mixture of two or more substances
Explanation :
A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.
[11] Choose the incorrect statement pertaining to organic compounds -
A.
They have low melting and boiling points
B.
They do not dissolve in water
C.
They are not easily combustible
D.
They contain mainly carbon and hydrogen
Ans:
They are not easily combustible
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.
[12] Which of the process is known as nitrification?
A.
Reaction of Nitrogen Monoxide with oxygen to form nitric acid
B.
Reaction of nitrogen dioxide with water to form nitric acid
C.
Conversion of ammonia to nitrites
D.
Conversion of nitrite to nitric oxide
Ans:
Conversion of ammonia to nitrites
Explanation :
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The oxidation of ammonia into nitrite is performed by two groups of organisms, ammonia-oxidizing bacteria AOB) and ammonia-oxidizing archaea (AOA). Nitrification is an important step in the nitrogen cycle in soil.
[13] Acid rain is caused due to pollution of atmosphere by –
A.
oxides of carbon and nitrogen
B.
oxides of nitrogen and sulphur
C.
oxides of nitrogen and phosphorous
D.
None of these
Ans:
oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.
[14] Neuron is -
A.
Fundamental unit of energy
B.
Particle released in radioactive emission
C.
Antiparbcle of neutron
D.
Fundamental unit of nervous system
Ans:
Fundamental unit of nervous system
Explanation :
A neuron is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon.
[15] Water cycle refers to –
A.
an integrated attempt to recycle water in relatively arid regions
B.
constant movement of water from ocean to land and back to ocean once again
C.
scientific management of water in areas excessively plagued with water-logging
D.
water distribution in relatively dry area
Ans:
constant movement of water from ocean to land and back to ocean once again
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
constant movement of water from ocean to land and back to ocean once again
[16] When a spoon is to be electroplated with nickel the spoon is -
A.
dipped in a nickel sulphate solution
B.
made anode and a pure nickel rod, the cathode
C.
made cathode and a pure nickel red, the anode
D.
coated with nickel sulphate and dried
Ans:
made cathode and a pure nickel red, the anode
Explanation :
Electroplating is the deposition by electrolysis of a coating of metal upon a conducting surface. The simplest system makes the object to be plated the negative electrode (cathode) or plate in a galvanic couple. Thus a spoon or other object may be connected by a wire to a plate of nickel. The process that occurs on the spoon is called reduction and, therefore, the spoon is also referred to as a cathode.
[17] Which of the following is not a method of preparing oxygen?
A.
Electrolysis of water
B.
Fractional distillation of liquid air
C.
Decomposition of potassium permanganate
D.
Decomposition of manganese dioxide
Ans:
Decomposition of manganese dioxide
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
One of the two chemical methods starts from natural manganese dioxide and converts it using dinitrogen tetroxide and water to manganese nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400°C, the salt decomposes, releasing N2O4 and leaving a residue of purified manganese dioxide.
[18] The mass number of a nucleus is -
A.
always less than its atomic number
B.
the sum of the number of protons and neutrons present in the nucleus
C.
always more than the atomic weight
D.
a fraction
Ans:
the sum of the number of protons and neutrons present in the nucleus
Explanation :
0
[19] Which one of the following takes place during a nuclear fusion?
A.
a heavy nucleus bombarded by neutrons breaks up
B.
a heavy nucleus breaks up spontaneously
C.
two light nuclei combine to form a heavy nucleus
D.
a light nucleus breaks up spontaneously
Ans:
two light nuclei combine to form a heavy nucleus
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. The difference in mass between the products and reactants is manifested as the release of large amounts of energy. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.
[20] Helium is added to the oxygen supply of deep sea divers because it is -
A.
less poisonous than nitrogen
B.
Lighter than nitrogen
C.
Readily miscible with oxygen
D.
less soluble in blood than nitrogen at high pressure
Ans:
less soluble in blood than nitrogen at high pressure
Explanation :
Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore is less soluble in blood than nitrogen and pre- vents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.
[21] The chemical bahaviour of an atom depends upon -
A.
the number of protons in its nucleus
B.
the number of neutrons in the nucleus
C.
the number of electrons orbiting around the nucleus
D.
the number of nucleons in the nucleus
Ans:
the number of electrons orbiting around the nucleus
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of the atom, the electron configuration determines how it will bond, with what it will bond, and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
[22] Methyl phenyl ether can be obtained by reacting -
A.
phenolate ions and methyl iodide
B.
methoxide ions and bromobenzene
C.
methanol and phenol
D.
bromobenzene and methyl bromide
Ans:
phenolate ions and methyl iodide
Explanation :
0
[23] Acid Rain is caused due to pollution of atmosphere by –
A.
Oxides of nitrogen and phosphorus
B.
Oxides of carbon and nitrogen
C.
Oxides of nitrogen and sulphur
D.
None of these
Ans:
Oxides of nitrogen and sulphur
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
Acid rain is caused by emissions of oxides of Sulfur and Nitrogen (Sulfur Dioxide and Nitrogen Oxide), which react with the water molecules in the atmosphere to produce acids. The emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) result from fossil fuel combustion.
[24] Air is said to be saturated when -
A.
it contains maximum content of water vapour
B.
its pressure is minimum
C.
its thickness is maximum
D.
it blows over the barren land
Ans:
it contains maximum content of water vapour
Explanation :
When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Mr is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.
[25] Which one of the following group of gases contribute to the "Green House Effect"?
A.
Carbon dioxide and Methane
B.
Ammonia and Ozone
C.
Carbon monoxide and Sulphur dioxide
D.
Carbon tetrailouride and Nitrous oxide
Ans:
Carbon dioxide and Methane
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.
Explanation :
The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.