[1] Threshold limit value of copper in the atmospheric air is -
A.
0.001 mg/m3
B.
0.01 mg/m3
C.
1.0 mg/m3
D.
5.0 mg/m3
Ans:
1.0 mg/m3
Explanation :
Inspirable copper dust takes a predominantly fibrous effect. The ALV of copper aerosol in the workplace atmosphere is 0.5 mg/m3, while the threshold limit value (TLV) is 1.0 mg/m3.
[2] Silicone is a polymer of –
A.
Tetraalkyl silane
B.
Silicon tetrachloride
C.
Dialkyl dichloro silane
D.
Silane
Ans:
Dialkyl dichloro silane
Explanation :
In order to manufacture silicones, alkyl-substituted chlorosilanes are used as starting material. Since dimethylsilane contains —OH group at the end of the chain, polymerization and chain length increases. However, the hydrolysis of alkyl trichlorosilane gives very complex cross linked polymer.
[3] Which is not an anasthetic agent in surgical operations?
A.
Chloroform
B.
Ether
C.
Nitrous oxide
D.
Acetone
Ans:
Acetone
Explanation :
The currently used inhalational anaesthetic agents are mainly: nitrous oxide, isoflurane, sevoflurane and desflurane. Chloroform, ether, ethylene are other an-aesthetic agents. However, they are not widely used in clinical practice today.
[4] Brass is an alloy of :
A.
Cu, Al and Zn
B.
Cu and Sn
C.
Cu and Zn
D.
Al and Mg
Ans:
Cu and Zn
Explanation :
Brass is an alloy made of copper and zinc. The proportions of zinc and copper can be varied to cre -ate a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin.
[5] Iron is prevented from rusting by coating with zinc. This process is called as –
A.
Galvanisation
B.
Corrosion
C.
Sublimation
D.
Reduction
Ans:
Galvanisation
Explanation :
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are sub-merged in a bath of molten zinc.
[6] Which of the following is the maximum number of electrons that can be present in M-shell?
A.
2
B.
8
C.
18
D.
32
Ans:
18
Explanation :
The maximum number of electrons that can occupy a specific energy level can be found using the following formula: Electron Capacity = 2n2. The variable n represents the Principal Quantum Number, the number of the energy level in question.
[7] Chemical that is used in photography -
A.
Copper sulphate
B.
Silver bromide
C.
Magnesium sulphate
D.
None
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr) is a soft pale-yellow, water insoluble salt well for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
[8] The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
A.
Nuclear fusion
B.
Nuclear fission
C.
Nuclear reaction
D.
Fast breeding
Ans:
Nuclear fission
Explanation :
Nuclear fission is a process used to create energy. It is when an atom splits apart into smaller atoms. The process gives off a lot of energy, and is used in nuclear weapons and nuclear reactors.
[9] Sodium Carbonate is commonly known as -
A.
Baking Soda
B.
Washing Soda
C.
Caustic Soda
D.
Caustic Potash
Ans:
Washing Soda
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Inspirable copper dust takes a predominantly fibrous effect. The ALV of copper aerosol in the workplace atmosphere is 0.5 mg/m3, while the threshold limit value (TLV) is 1.0 mg/m3.
[2] Silicone is a polymer of –
A.
Tetraalkyl silane
B.
Silicon tetrachloride
C.
Dialkyl dichloro silane
D.
Silane
Ans:
Dialkyl dichloro silane
Explanation :
In order to manufacture silicones, alkyl-substituted chlorosilanes are used as starting material. Since dimethylsilane contains —OH group at the end of the chain, polymerization and chain length increases. However, the hydrolysis of alkyl trichlorosilane gives very complex cross linked polymer.
[3] Which is not an anasthetic agent in surgical operations?
A.
Chloroform
B.
Ether
C.
Nitrous oxide
D.
Acetone
Ans:
Acetone
Explanation :
The currently used inhalational anaesthetic agents are mainly: nitrous oxide, isoflurane, sevoflurane and desflurane. Chloroform, ether, ethylene are other an-aesthetic agents. However, they are not widely used in clinical practice today.
[4] Brass is an alloy of :
A.
Cu, Al and Zn
B.
Cu and Sn
C.
Cu and Zn
D.
Al and Mg
Ans:
Cu and Zn
Explanation :
Brass is an alloy made of copper and zinc. The proportions of zinc and copper can be varied to cre -ate a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin.
[5] Iron is prevented from rusting by coating with zinc. This process is called as –
A.
Galvanisation
B.
Corrosion
C.
Sublimation
D.
Reduction
Ans:
Galvanisation
Explanation :
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are sub-merged in a bath of molten zinc.
[6] Which of the following is the maximum number of electrons that can be present in M-shell?
A.
2
B.
8
C.
18
D.
32
Ans:
18
Explanation :
The maximum number of electrons that can occupy a specific energy level can be found using the following formula: Electron Capacity = 2n2. The variable n represents the Principal Quantum Number, the number of the energy level in question.
[7] Chemical that is used in photography -
A.
Copper sulphate
B.
Silver bromide
C.
Magnesium sulphate
D.
None
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr) is a soft pale-yellow, water insoluble salt well for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
[8] The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
A.
Nuclear fusion
B.
Nuclear fission
C.
Nuclear reaction
D.
Fast breeding
Ans:
Nuclear fission
Explanation :
Nuclear fission is a process used to create energy. It is when an atom splits apart into smaller atoms. The process gives off a lot of energy, and is used in nuclear weapons and nuclear reactors.
[9] Sodium Carbonate is commonly known as -
A.
Baking Soda
B.
Washing Soda
C.
Caustic Soda
D.
Caustic Potash
Ans:
Washing Soda
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
The currently used inhalational anaesthetic agents are mainly: nitrous oxide, isoflurane, sevoflurane and desflurane. Chloroform, ether, ethylene are other an-aesthetic agents. However, they are not widely used in clinical practice today.
[4] Brass is an alloy of :
A.
Cu, Al and Zn
B.
Cu and Sn
C.
Cu and Zn
D.
Al and Mg
Ans:
Cu and Zn
Explanation :
Brass is an alloy made of copper and zinc. The proportions of zinc and copper can be varied to cre -ate a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin.
[5] Iron is prevented from rusting by coating with zinc. This process is called as –
A.
Galvanisation
B.
Corrosion
C.
Sublimation
D.
Reduction
Ans:
Galvanisation
Explanation :
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are sub-merged in a bath of molten zinc.
[6] Which of the following is the maximum number of electrons that can be present in M-shell?
A.
2
B.
8
C.
18
D.
32
Ans:
18
Explanation :
The maximum number of electrons that can occupy a specific energy level can be found using the following formula: Electron Capacity = 2n2. The variable n represents the Principal Quantum Number, the number of the energy level in question.
[7] Chemical that is used in photography -
A.
Copper sulphate
B.
Silver bromide
C.
Magnesium sulphate
D.
None
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr) is a soft pale-yellow, water insoluble salt well for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
[8] The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
A.
Nuclear fusion
B.
Nuclear fission
C.
Nuclear reaction
D.
Fast breeding
Ans:
Nuclear fission
Explanation :
Nuclear fission is a process used to create energy. It is when an atom splits apart into smaller atoms. The process gives off a lot of energy, and is used in nuclear weapons and nuclear reactors.
[9] Sodium Carbonate is commonly known as -
A.
Baking Soda
B.
Washing Soda
C.
Caustic Soda
D.
Caustic Potash
Ans:
Washing Soda
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are sub-merged in a bath of molten zinc.
[6] Which of the following is the maximum number of electrons that can be present in M-shell?
A.
2
B.
8
C.
18
D.
32
Ans:
18
Explanation :
The maximum number of electrons that can occupy a specific energy level can be found using the following formula: Electron Capacity = 2n2. The variable n represents the Principal Quantum Number, the number of the energy level in question.
[7] Chemical that is used in photography -
A.
Copper sulphate
B.
Silver bromide
C.
Magnesium sulphate
D.
None
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr) is a soft pale-yellow, water insoluble salt well for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
[8] The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
A.
Nuclear fusion
B.
Nuclear fission
C.
Nuclear reaction
D.
Fast breeding
Ans:
Nuclear fission
Explanation :
Nuclear fission is a process used to create energy. It is when an atom splits apart into smaller atoms. The process gives off a lot of energy, and is used in nuclear weapons and nuclear reactors.
[9] Sodium Carbonate is commonly known as -
A.
Baking Soda
B.
Washing Soda
C.
Caustic Soda
D.
Caustic Potash
Ans:
Washing Soda
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Silver bromide (AgBr) is a soft pale-yellow, water insoluble salt well for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials.
[8] The nuclear reaction in which a heavy nucleus splits into two nuclei of nearly equal mass is called -
A.
Nuclear fusion
B.
Nuclear fission
C.
Nuclear reaction
D.
Fast breeding
Ans:
Nuclear fission
Explanation :
Nuclear fission is a process used to create energy. It is when an atom splits apart into smaller atoms. The process gives off a lot of energy, and is used in nuclear weapons and nuclear reactors.
[9] Sodium Carbonate is commonly known as -
A.
Baking Soda
B.
Washing Soda
C.
Caustic Soda
D.
Caustic Potash
Ans:
Washing Soda
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Sodium carbonate (Na2CO3) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.
[10] When a bond is formed between two atoms, the energy of the sys-tem will –
A.
increase
B.
decrease
C.
remain the same
D.
may increase or decrease
Ans:
remain the same
Explanation :
The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential enemy is always released to the surroundings.
[11] The ore of Aluminium is -
A.
Fluorspar
B.
Bauxite
C.
Chalco pyrites
D.
Hematite
Ans:
Bauxite
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Bauxite, an aluminium ore, is the world's main source of aluminium. Bauxite is priinarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. It is refined through the Bayer chemical process into alumina.
[12] Which of the following molecules or ions involved in the Nitrogen Cycle do not contain oxygen atom?
A.
Nitrite
B.
Ammonia
C.
Nitrate
D.
Laughing gas
Ans:
Ammonia
Explanation :
0
[13] Which of the following is used as a coolant in nuclear reactors?
A.
Heavy water
B.
Cadmium
C.
Liquid sodium
D.
Graphite
Ans:
Liquid sodium
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. Sodium has only one stable isotope, sodium-23. Sodium-23 is a very weak absorber of neutrons.
[14] lodex, a pain relief balm, has the smell of _.
A.
Methyl salicylate
B.
Ethyl salicylate
C.
Propyl salicylate
D.
Butyl salicylate
Ans:
Methyl salicylate
Explanation :
Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.
[15] A complex compound in which the oxidation number of a metal is zero is -
A.
K4 [Fe (CN)6]
B.
K3 [Fe (CN)6]
C.
[Ni (CO)4]
D.
[Pl (NH3)4]Cl2
Ans:
[Ni (CO)4]
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
[16] What is a Bakelite?
A.
Solution
B.
Acid
C.
Base
D.
Polymer
Ans:
Polymer
Explanation :
Bakelite is the commercial name for the polymer obtained by the polymerization of phenol and formaldehyde. It is an early plastic. Plastic (from the Greek "plastikos," meaning moldable) is the popular term for a variety of synthetic, or manmade, polymers. Bakelite was developed by the Belgian- American chemist Leo Baekeland in New York in 1907.
[17] What do you understand by the term Espuma?
A.
Foam
B.
Soap
C.
Salt
D.
Calcium
Ans:
Foam
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Espuma is a Spanish term for froth or foam, and one that is created specifically with the use of a siphon bottle. Espuma is created mainly with liquid that has air incorporated in it to create froth. This is a specific term, since culinary foams may be attained through other means.
[18] The element used for vulcanizing rubber is -
A.
Sulphur
B.
Bromine
C.
Silicon
D.
Phosphorus
Ans:
Sulphur
Explanation :
The vulcanization of neoprene or polychloroprene rubber (CR rubber) is carried out using metal oxides (specifically MgO and ZnO, sometimes Pb3O4) rather than sulfur compounds which are presently used with many natural and synthetic rubbers.
[19] Which of the following is used as lubricant?
A.
Graphite
B.
Silica
C.
Diamond
D.
Iron Oxide
Ans:
Graphite
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Graphite is used as a lubricant due to its slippery nature. Due to its loosely intact carbon atoms or free electrons, they can move around easily from one place to another, making graphite a good conductor of electricity.
[20] Heavy metals got their name because compared to other atoms they have -
A.
Higher densities
B.
Higher atomic masses
C.
Higher atomic numbers
D.
Higher atomic radii
Ans:
Higher atomic masses
Explanation :
Arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium are some of the metals called 'heavy' because of their high relative atomic mass. They persist in nature and can cause damage or death in animals, humans, and plants even at very low concentrations.
[21] Concentration of a material which is lethal to 50% animal is called–
A.
LD50
B.
LC50
C.
NOAEL
D.
ADI
Ans:
LD50
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
LD50 (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD50 is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC50 is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.
[22] Muddy water is treated with alum in purification process, it is termed as :
A.
emulsification
B.
absorption
C.
adsorption
D.
coagulation
Ans:
coagulation
Explanation :
Natural and wastewater contain small particulates that are suspended in water forming a colloid. These particles carry the same charges, and repulsion prevents them from combining into larger particulates to settle.
[23] ‘Plaster of pans’ chemically known as -
A.
Sodium Aluminate
B.
Calcium sulphate
C.
Spdium bicarbonate
D.
Sodium acetate
Ans:
Calcium sulphate
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Calcium sulphate is a calcium salt that is used for a variety of purposes. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.
[24] Which mineral is the ore of aluminium?
A.
Haematite
B.
Bauxite
C.
Magnetite
D.
Siderite
Ans:
Bauxite
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis.
[25] Which gas is used for converting vegetable oils into saturated fats?
A.
H2
B.
O2
C.
Cl2
D.
SO2
Ans:
H2
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).
Explanation :
Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst. The largest scale application of hydrogenation is for the processing of vegetable oils (fats to give margarine and related spreads and shortenings). Typical vegetable oils are derived from polyunsaturated fatty acids (containing more than one carbon-carbon double bonds).