[1] The purest form of water in nature is –
A.
Rain water
B.
Lake water
C.
River water
D.
Sea water
Ans:
Rain water
Explanation :
Rainwater is often considered the purest form of water available on the Earth. The evaporation of water by the sun allows the salts and other impurities to be left behind out of the water. However, in reality, rain water is often much less than pure when it reaches the surface of the Earth due to the high pollution of air with toxic gases.
[2] The element used for making solar cells is -
A.
Magnesium
B.
Sodium
C.
Calcium
D.
Silicon
Ans:
Silicon
Explanation :
Materials presently used for photovoltaic solar cells include mono-crystalline silicon, polycrystaijhne silicon, amorphous silicon, cadmium telluride, and copper indium selenideisulfide.
[3] What is the number of atoms constituting a molecule known as -
A.
Atomic number
B.
Isotopes
C.
Atomic mass
D.
Atomicity
Ans:
Atomicity
Explanation :
Atomicity is the total number of atoms present in one molecule of an element.
[4] If water smells bad, then that odour can be removed by adding -
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foulodor.
[5] Substance used as an anti-freeze in radiators of automobiles is :
A.
Methyl alcohol and H2O
B.
Methy] alcohol
C.
Ethyl alcohol
D.
Ethyl alcohol and H2O
Ans:
Methyl alcohol and H2O
Explanation :
Methyl alcohol and water are used as an anti-freeze in radiators of automobiles.
[6] The function of sedimentation tank in sewage treatment is to:
A.
Disinfect the sewage
B.
Remove water content
C.
Aerate the sewage
D.
Remove suspended solids
Ans:
Remove suspended solids
Explanation :
The function of sedimentation tank in the sewage treatment is to remove suspended solids.
[7] Which of the following is a method/process of disposing of solid waste which cannot be re-used or recycled?
A.
Landfills
B.
Incineration
C.
Pyrolysis and Gasification
D.
An the above
Ans:
An the above
Explanation :
Landfills, Incineration, Pyrolysis and Gasification are methods of disposing of solid waste which cannot be reused or recycled.
[8] The weight of 6.023 x 1022 atoms of carbon is –
A.
12 gms
B.
120 gms
C.
1.2 gms
D.
0.12 gms
Ans:
12 gms
Explanation :
The number is known as Avogadro's Number which is the number of atoms in 12g of the isotope carbon-12. carbon atoms weigh = 12 grams.
[9] Sulphur dioxide bleaches colouring matter by –
A.
Reduction
B.
Dehydration
C.
Decomposition
D.
Oxidation
Ans:
Reduction
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Rainwater is often considered the purest form of water available on the Earth. The evaporation of water by the sun allows the salts and other impurities to be left behind out of the water. However, in reality, rain water is often much less than pure when it reaches the surface of the Earth due to the high pollution of air with toxic gases.
[2] The element used for making solar cells is -
A.
Magnesium
B.
Sodium
C.
Calcium
D.
Silicon
Ans:
Silicon
Explanation :
Materials presently used for photovoltaic solar cells include mono-crystalline silicon, polycrystaijhne silicon, amorphous silicon, cadmium telluride, and copper indium selenideisulfide.
[3] What is the number of atoms constituting a molecule known as -
A.
Atomic number
B.
Isotopes
C.
Atomic mass
D.
Atomicity
Ans:
Atomicity
Explanation :
Atomicity is the total number of atoms present in one molecule of an element.
[4] If water smells bad, then that odour can be removed by adding -
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foulodor.
[5] Substance used as an anti-freeze in radiators of automobiles is :
A.
Methyl alcohol and H2O
B.
Methy] alcohol
C.
Ethyl alcohol
D.
Ethyl alcohol and H2O
Ans:
Methyl alcohol and H2O
Explanation :
Methyl alcohol and water are used as an anti-freeze in radiators of automobiles.
[6] The function of sedimentation tank in sewage treatment is to:
A.
Disinfect the sewage
B.
Remove water content
C.
Aerate the sewage
D.
Remove suspended solids
Ans:
Remove suspended solids
Explanation :
The function of sedimentation tank in the sewage treatment is to remove suspended solids.
[7] Which of the following is a method/process of disposing of solid waste which cannot be re-used or recycled?
A.
Landfills
B.
Incineration
C.
Pyrolysis and Gasification
D.
An the above
Ans:
An the above
Explanation :
Landfills, Incineration, Pyrolysis and Gasification are methods of disposing of solid waste which cannot be reused or recycled.
[8] The weight of 6.023 x 1022 atoms of carbon is –
A.
12 gms
B.
120 gms
C.
1.2 gms
D.
0.12 gms
Ans:
12 gms
Explanation :
The number is known as Avogadro's Number which is the number of atoms in 12g of the isotope carbon-12. carbon atoms weigh = 12 grams.
[9] Sulphur dioxide bleaches colouring matter by –
A.
Reduction
B.
Dehydration
C.
Decomposition
D.
Oxidation
Ans:
Reduction
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Atomicity is the total number of atoms present in one molecule of an element.
[4] If water smells bad, then that odour can be removed by adding -
A.
alum
B.
bleach
C.
activated carbon
D.
deactivated nitrogen
Ans:
activated carbon
Explanation :
Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foulodor.
[5] Substance used as an anti-freeze in radiators of automobiles is :
A.
Methyl alcohol and H2O
B.
Methy] alcohol
C.
Ethyl alcohol
D.
Ethyl alcohol and H2O
Ans:
Methyl alcohol and H2O
Explanation :
Methyl alcohol and water are used as an anti-freeze in radiators of automobiles.
[6] The function of sedimentation tank in sewage treatment is to:
A.
Disinfect the sewage
B.
Remove water content
C.
Aerate the sewage
D.
Remove suspended solids
Ans:
Remove suspended solids
Explanation :
The function of sedimentation tank in the sewage treatment is to remove suspended solids.
[7] Which of the following is a method/process of disposing of solid waste which cannot be re-used or recycled?
A.
Landfills
B.
Incineration
C.
Pyrolysis and Gasification
D.
An the above
Ans:
An the above
Explanation :
Landfills, Incineration, Pyrolysis and Gasification are methods of disposing of solid waste which cannot be reused or recycled.
[8] The weight of 6.023 x 1022 atoms of carbon is –
A.
12 gms
B.
120 gms
C.
1.2 gms
D.
0.12 gms
Ans:
12 gms
Explanation :
The number is known as Avogadro's Number which is the number of atoms in 12g of the isotope carbon-12. carbon atoms weigh = 12 grams.
[9] Sulphur dioxide bleaches colouring matter by –
A.
Reduction
B.
Dehydration
C.
Decomposition
D.
Oxidation
Ans:
Reduction
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Methyl alcohol and water are used as an anti-freeze in radiators of automobiles.
[6] The function of sedimentation tank in sewage treatment is to:
A.
Disinfect the sewage
B.
Remove water content
C.
Aerate the sewage
D.
Remove suspended solids
Ans:
Remove suspended solids
Explanation :
The function of sedimentation tank in the sewage treatment is to remove suspended solids.
[7] Which of the following is a method/process of disposing of solid waste which cannot be re-used or recycled?
A.
Landfills
B.
Incineration
C.
Pyrolysis and Gasification
D.
An the above
Ans:
An the above
Explanation :
Landfills, Incineration, Pyrolysis and Gasification are methods of disposing of solid waste which cannot be reused or recycled.
[8] The weight of 6.023 x 1022 atoms of carbon is –
A.
12 gms
B.
120 gms
C.
1.2 gms
D.
0.12 gms
Ans:
12 gms
Explanation :
The number is known as Avogadro's Number which is the number of atoms in 12g of the isotope carbon-12. carbon atoms weigh = 12 grams.
[9] Sulphur dioxide bleaches colouring matter by –
A.
Reduction
B.
Dehydration
C.
Decomposition
D.
Oxidation
Ans:
Reduction
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Landfills, Incineration, Pyrolysis and Gasification are methods of disposing of solid waste which cannot be reused or recycled.
[8] The weight of 6.023 x 1022 atoms of carbon is –
A.
12 gms
B.
120 gms
C.
1.2 gms
D.
0.12 gms
Ans:
12 gms
Explanation :
The number is known as Avogadro's Number which is the number of atoms in 12g of the isotope carbon-12. carbon atoms weigh = 12 grams.
[9] Sulphur dioxide bleaches colouring matter by –
A.
Reduction
B.
Dehydration
C.
Decomposition
D.
Oxidation
Ans:
Reduction
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Sulphur dioxide gas exhibits bleaching properties in presence of moisture. It dissolves in water liberating nascent hydrogen. Nascent hydrogen removes oxygen atoms from the colouring matter (reduces colouring matter) and it loses its colour.
[10] Which of the following elements is not radioactive?
A.
Radium
B.
Plutonium
C.
Zirconium
D.
Uranium
Ans:
Zirconium
Explanation :
Zireonium is a lustrous, grey-white, strong transition metal that resembles titanium. Zirconium is mainly used as a refractory and pacifier, although it is used in small amounts as an alloying agent for its strong resistance to corrosion.
[11] KMnO4 can be used as –
A.
Insecticide
B.
Fertilizer
C.
Pesticide
D.
Disinfectant
Ans:
Disinfectant
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Potassium permanganate is an inorganic chemical compound with the formula KMnO4. As an oxidant, potassium permanganate can act as an antiseptic. For example, dilute solutions are used to treat canker sores (ulcers), disinfectant for the hands and treatment for mild pompholyx, dermatitis, and fungal infections of the hands or feet. Potassium permanganate is used extensively in the water treatment industry.
[12] A thick paste of cement, sand and water is called –
A.
Concrete
B.
R.C.C.
C.
Mortar
D.
Kiln
Ans:
Mortar
Explanation :
Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water
[13] Which one of the following metals pollutes the air of a city having large number of automobiles?
A.
Cadmium
B.
Chromium
C.
Lead
D.
Copper
Ans:
Lead
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
The history of car pollution has been one of air and water contamination followed by regulated improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent.
[14] `Milk of Magnesia' is a suspension of –
A.
magnesium sulphate
B.
magnesium carbonate
C.
magnesium hydroxide
D.
magnesium chloride
Ans:
magnesium hydroxide
Explanation :
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance.
[15] Pollutant from motor car exhaust that causes mental disease is –
A.
Lead
B.
NO2
C.
SO2
D.
Hg
Ans:
Lead
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Lead poisoning is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system, and is therefore particularly toxic to children.
[16] The total energy of revolving electron in an atom –
A.
cannot be negative
B.
can have any value above zero
C.
can never be positive
D.
will always be positive
Ans:
can never be positive
Explanation :
The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energ ies. Energy of an electron at infinite distance from the nucleus is zero. As an electron approaches the nucleus, the electron attraction increase and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
[17] The chief source for the production of nitrogeneous fertilizers is :
A.
Ammonia
B.
Nitric acid
C.
Nitrogen
D.
Nitrogen dioxide
Ans:
Ammonia
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Nitrogen fertilizers are often made using the Haber-Bosch process which uses natural gas for the hydrogen and nitrogen gas from the air at an elevated temperature and pressure in the presence of a catalyst to form ammonia as the end product. This ammonia is used as a feedstock for other nitrogen fertilizers, such as anhydrous ammonium nitrate and urea.
[18] Zn + 2 HCl = H2 + ZnCl, is an example of which type of reaction?
A.
Double displacement reaction
B.
Combination reaction
C.
Single displacement reaction
D.
Decomposition reaction
Ans:
Single displacement reaction
Explanation :
This reaction is an example of single displacement reaction. In Substitution or Single Replacement Reactions, a single free element replaces or is substituted for one of the elements in a compound.
[19] Which of the following is not a natural polymer?
A.
Wool
B.
Silk
C.
Cotton
D.
Teflon
Ans:
Teflon
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Natural polymers occur in nature and can be extracted. They are often water-based. Examples of naturally occurring polymers are silk, wool, DNA, cellulose, cotton and proteins.
[20] Vulcanized rubber contains sulphur –
A.
0.02
B.
3-5%
C.
7-9%
D.
I 0- 5%
Ans:
3-5%
Explanation :
A vulcanized flexible tyre rubber contains about 3 -5% of sulphur whereas hard rubber (ebonite) contains about 32% of sulphur. The stiffness of vulcanized rubber depends on the amount of sulphur added.
[21] Which of the following is a metallic ore?
A.
Mica
B.
Quartz
C.
Feldspar
D.
Galena
Ans:
Galena
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Galena is the most abundant lead mineral. It is a metallic, lead-gray mineral with cubic cleavage and a distinctly high density. It belongs to the octahedral sulfide group of minerals with metal ions in octahedral positions.
[22] The first organic compound synthesized in the laboratory was -
A.
Urea
B.
Uric acid
C.
Lactic acid
D.
Glucose
Ans:
Urea
Explanation :
In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound).
[23] The green colour seen in firework displays is due to the chloride salt of–
A.
Sodium
B.
Strontium
C.
Barium
D.
Calcium
Ans:
Barium
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
The red, orange, yellow, green, blue and purple colors exploding in the night sky during a pyrotechnic festival are created by the use of metal salts. Barium chloride provides green colour to firework displays. Metal salts that are commonly used in fire-work displays include: strontium carbonate (red), calcium chloride (orange), sodium nitrate (yellow), barium chloride (green fireworks) and copper chloride (blue fireworks).
[24] The radiation that can penetrate deepest in our body –
A.
UV-radiation
B.
Alpha-particles
C.
a-particles
D.
Gamma-particles
Ans:
Gamma-particles
Explanation :
The ability of radioactivity to pass through materials is called its penetrating ability. Penetrating ability depends on the size of the radioactive particle. Alpha particles are the biggest, beta particles are very much smaller and gamma rays have no mass.
[25] Which radioactive pollutant has recently drawn the attention of the public due to its occurrence in the building materials?
A.
Radium
B.
Radon
C.
Thorium
D.
Rlutonium
Ans:
Thorium
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.
Explanation :
Thorium, a naturally occurring radioactive element, four times more abundant than uranium in the earth's crust.