[1] Bhopal has tragedy is associated with leakage of –
A.
carbon dioxide
B.
nitrogen dioxide
C.
sulphur dioxide
D.
methyl isocyanate
Ans:
methyl isocyanate
Explanation :
The Bhopal disaster, also referred to as the Bhopal has tragedy, was a gas leak incident in India, considered one of the world's worst industrial disasters. It occurred on the night of 2-3 December, 1984 at the Union Carbide India Limited (UCIL) pesticide plant in Bhopal, Madhya Pradesh. Over 500,000 people were exposed to methyl isocyanate gas and other chemicals. The toxic substance made its way in and around the shantytowns located near the plant.
[2] Bauxite is an alloy of which of the following metals?
A.
Aluminium
B.
Silver
C.
Tin
D.
Iron
Ans:
Aluminium
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. This form of rock consists mostly of the minerals gibbsite Al(OH)3, boehmite, and diaspore, in a mixture with the two iron oxides goethite and hematite, the clay mineral kaolinite, and small amounts of anatase TiO2.
[3] Nucleus of an atom consists of.
A.
Proton
B.
Neutron
C.
Proton and Neutron
D.
Electron, Proton and Neutron
Ans:
Proton and Neutron
Explanation :
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The proton-neutron model of nucleus was proposed by Dmitry Ivanenko in 1932. Almost all of the mass of an atom is located in the nucleus, with a very small contribution from the orbiting electrons.
[4] Where does the oxygen that keeps us alive come from?
A.
Carbon dioxide
B.
Carbonates absorbed from soil
C.
Oxides of minerals
D.
Water
Ans:
Water
Explanation :
Since water and carbon dioxide are both compounds which contain oxygen, it is possible to obtain oxygen from either. The oxygen produced from photosynthesis is not released into the air. It is not until cellular respiration that oxygen is released. The oxygen comes from water. The water molecules are split at the "beginning" of photosynthesis for the electrons. These electrons eventually make their way to the electron transport chain, where oxygen is the final electron accept, and then released into the air. Scientists agree that there's oxygen from ocean plants in every breath we take.
[5] The gas used for artificial fruit ripening of green fruit is –
A.
Ethylent
B.
Acetylene
C.
Ethane
D.
Methane
Ans:
Ethylent
Explanation :
Ethylene can promote ripening in tomatoes, bananas, citrus, pineapples, dates, persimmons, pears, apples, melons, mangos, avocados, papayas and jujubes - a clear indication that the action of ethylene is general and widespread amongst a number of fruits. It is clear that ethylene is a ripening hormone - a chemical substance produced by fruits with the specific biological phenomenon of accelerating the normal process of fruit maturation and senescence.
[6] Magnets attract magnetic substances are iron, nickel, cobalt, etc. They can also repel -
A.
paramagnetic substances
B.
ferromagnetic substances
C.
diamagnetic substances
D.
non-magnetic substances
Ans:
diamagnetic substances
Explanation :
Those materials which when placed in a magnetic field become weakly magnetized in a direction opposite to that of the applied field, are called as diamagnetic materials. Example: bismuth, antimony, copper, gold, quartz, mercury, water, alcohol, air, hydrogen etc.
[7] Atomic mass of Sulphur is 32u. The number of moles in 16 games of Sulphur is:
A.
1 mole of Sulphur
B.
0.5 moles of Sulphur
C.
0.75 moles of Sulphur
D.
0.25 moles of Sulphur
Ans:
0.5 moles of Sulphur
Explanation :
The molar mass of a com pound is equal to the sum of the atomic masses of its con stituent atoms in g/mol.
[8] A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be –
A.
silver
B.
copper
C.
aluminium
D.
zinc
Ans:
copper
Explanation :
Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion.
[9] Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers, etc.?
A.
Iron and cadmium
B.
Nickel and cadmium
C.
Lead peroxide and lead
D.
Zinc and carbon
Ans:
Nickel and cadmium
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
The Bhopal disaster, also referred to as the Bhopal has tragedy, was a gas leak incident in India, considered one of the world's worst industrial disasters. It occurred on the night of 2-3 December, 1984 at the Union Carbide India Limited (UCIL) pesticide plant in Bhopal, Madhya Pradesh. Over 500,000 people were exposed to methyl isocyanate gas and other chemicals. The toxic substance made its way in and around the shantytowns located near the plant.
[2] Bauxite is an alloy of which of the following metals?
A.
Aluminium
B.
Silver
C.
Tin
D.
Iron
Ans:
Aluminium
Explanation :
Bauxite is an aluminium ore and is the main source of aluminium. This form of rock consists mostly of the minerals gibbsite Al(OH)3, boehmite, and diaspore, in a mixture with the two iron oxides goethite and hematite, the clay mineral kaolinite, and small amounts of anatase TiO2.
[3] Nucleus of an atom consists of.
A.
Proton
B.
Neutron
C.
Proton and Neutron
D.
Electron, Proton and Neutron
Ans:
Proton and Neutron
Explanation :
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The proton-neutron model of nucleus was proposed by Dmitry Ivanenko in 1932. Almost all of the mass of an atom is located in the nucleus, with a very small contribution from the orbiting electrons.
[4] Where does the oxygen that keeps us alive come from?
A.
Carbon dioxide
B.
Carbonates absorbed from soil
C.
Oxides of minerals
D.
Water
Ans:
Water
Explanation :
Since water and carbon dioxide are both compounds which contain oxygen, it is possible to obtain oxygen from either. The oxygen produced from photosynthesis is not released into the air. It is not until cellular respiration that oxygen is released. The oxygen comes from water. The water molecules are split at the "beginning" of photosynthesis for the electrons. These electrons eventually make their way to the electron transport chain, where oxygen is the final electron accept, and then released into the air. Scientists agree that there's oxygen from ocean plants in every breath we take.
[5] The gas used for artificial fruit ripening of green fruit is –
A.
Ethylent
B.
Acetylene
C.
Ethane
D.
Methane
Ans:
Ethylent
Explanation :
Ethylene can promote ripening in tomatoes, bananas, citrus, pineapples, dates, persimmons, pears, apples, melons, mangos, avocados, papayas and jujubes - a clear indication that the action of ethylene is general and widespread amongst a number of fruits. It is clear that ethylene is a ripening hormone - a chemical substance produced by fruits with the specific biological phenomenon of accelerating the normal process of fruit maturation and senescence.
[6] Magnets attract magnetic substances are iron, nickel, cobalt, etc. They can also repel -
A.
paramagnetic substances
B.
ferromagnetic substances
C.
diamagnetic substances
D.
non-magnetic substances
Ans:
diamagnetic substances
Explanation :
Those materials which when placed in a magnetic field become weakly magnetized in a direction opposite to that of the applied field, are called as diamagnetic materials. Example: bismuth, antimony, copper, gold, quartz, mercury, water, alcohol, air, hydrogen etc.
[7] Atomic mass of Sulphur is 32u. The number of moles in 16 games of Sulphur is:
A.
1 mole of Sulphur
B.
0.5 moles of Sulphur
C.
0.75 moles of Sulphur
D.
0.25 moles of Sulphur
Ans:
0.5 moles of Sulphur
Explanation :
The molar mass of a com pound is equal to the sum of the atomic masses of its con stituent atoms in g/mol.
[8] A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be –
A.
silver
B.
copper
C.
aluminium
D.
zinc
Ans:
copper
Explanation :
Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion.
[9] Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers, etc.?
A.
Iron and cadmium
B.
Nickel and cadmium
C.
Lead peroxide and lead
D.
Zinc and carbon
Ans:
Nickel and cadmium
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The proton-neutron model of nucleus was proposed by Dmitry Ivanenko in 1932. Almost all of the mass of an atom is located in the nucleus, with a very small contribution from the orbiting electrons.
[4] Where does the oxygen that keeps us alive come from?
A.
Carbon dioxide
B.
Carbonates absorbed from soil
C.
Oxides of minerals
D.
Water
Ans:
Water
Explanation :
Since water and carbon dioxide are both compounds which contain oxygen, it is possible to obtain oxygen from either. The oxygen produced from photosynthesis is not released into the air. It is not until cellular respiration that oxygen is released. The oxygen comes from water. The water molecules are split at the "beginning" of photosynthesis for the electrons. These electrons eventually make their way to the electron transport chain, where oxygen is the final electron accept, and then released into the air. Scientists agree that there's oxygen from ocean plants in every breath we take.
[5] The gas used for artificial fruit ripening of green fruit is –
A.
Ethylent
B.
Acetylene
C.
Ethane
D.
Methane
Ans:
Ethylent
Explanation :
Ethylene can promote ripening in tomatoes, bananas, citrus, pineapples, dates, persimmons, pears, apples, melons, mangos, avocados, papayas and jujubes - a clear indication that the action of ethylene is general and widespread amongst a number of fruits. It is clear that ethylene is a ripening hormone - a chemical substance produced by fruits with the specific biological phenomenon of accelerating the normal process of fruit maturation and senescence.
[6] Magnets attract magnetic substances are iron, nickel, cobalt, etc. They can also repel -
A.
paramagnetic substances
B.
ferromagnetic substances
C.
diamagnetic substances
D.
non-magnetic substances
Ans:
diamagnetic substances
Explanation :
Those materials which when placed in a magnetic field become weakly magnetized in a direction opposite to that of the applied field, are called as diamagnetic materials. Example: bismuth, antimony, copper, gold, quartz, mercury, water, alcohol, air, hydrogen etc.
[7] Atomic mass of Sulphur is 32u. The number of moles in 16 games of Sulphur is:
A.
1 mole of Sulphur
B.
0.5 moles of Sulphur
C.
0.75 moles of Sulphur
D.
0.25 moles of Sulphur
Ans:
0.5 moles of Sulphur
Explanation :
The molar mass of a com pound is equal to the sum of the atomic masses of its con stituent atoms in g/mol.
[8] A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be –
A.
silver
B.
copper
C.
aluminium
D.
zinc
Ans:
copper
Explanation :
Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion.
[9] Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers, etc.?
A.
Iron and cadmium
B.
Nickel and cadmium
C.
Lead peroxide and lead
D.
Zinc and carbon
Ans:
Nickel and cadmium
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Ethylene can promote ripening in tomatoes, bananas, citrus, pineapples, dates, persimmons, pears, apples, melons, mangos, avocados, papayas and jujubes - a clear indication that the action of ethylene is general and widespread amongst a number of fruits. It is clear that ethylene is a ripening hormone - a chemical substance produced by fruits with the specific biological phenomenon of accelerating the normal process of fruit maturation and senescence.
[6] Magnets attract magnetic substances are iron, nickel, cobalt, etc. They can also repel -
A.
paramagnetic substances
B.
ferromagnetic substances
C.
diamagnetic substances
D.
non-magnetic substances
Ans:
diamagnetic substances
Explanation :
Those materials which when placed in a magnetic field become weakly magnetized in a direction opposite to that of the applied field, are called as diamagnetic materials. Example: bismuth, antimony, copper, gold, quartz, mercury, water, alcohol, air, hydrogen etc.
[7] Atomic mass of Sulphur is 32u. The number of moles in 16 games of Sulphur is:
A.
1 mole of Sulphur
B.
0.5 moles of Sulphur
C.
0.75 moles of Sulphur
D.
0.25 moles of Sulphur
Ans:
0.5 moles of Sulphur
Explanation :
The molar mass of a com pound is equal to the sum of the atomic masses of its con stituent atoms in g/mol.
[8] A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be –
A.
silver
B.
copper
C.
aluminium
D.
zinc
Ans:
copper
Explanation :
Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion.
[9] Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers, etc.?
A.
Iron and cadmium
B.
Nickel and cadmium
C.
Lead peroxide and lead
D.
Zinc and carbon
Ans:
Nickel and cadmium
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
The molar mass of a com pound is equal to the sum of the atomic masses of its con stituent atoms in g/mol.
[8] A metal is exposed to the atmosphere for some time. It becomes coated with green carbonate. The metal must be –
A.
silver
B.
copper
C.
aluminium
D.
zinc
Ans:
copper
Explanation :
Copper forms a rich variety of compounds with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. It does not react with water, but it slowly reacts with atmospheric oxygen forming a layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this oxide layer stops the further, bulk corrosion.
[9] Which of the following pairs of materials serves as electrodes in chargeable batteries commonly used in devices such as torch lights, electric shavers, etc.?
A.
Iron and cadmium
B.
Nickel and cadmium
C.
Lead peroxide and lead
D.
Zinc and carbon
Ans:
Nickel and cadmium
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
A rechargeable battery, storage battery, or accumulator is a type of electrical battery. It comprises one or more electrochemical cells, and is a type of energy accumulator. It is known as a secondary cell because its electrochemical reactions are electrically reversible. Rechargeable batteries come in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
[10] Iodized salt is beneficial for –
A.
lowering of blood pressure
B.
prevention of dehydration
C.
thyroid function
D.
salivary glands
Ans:
thyroid function
Explanation :
Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodide prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of mental retardation. Deficiency also causes thyroid gland problems, including "endemic goitre." In many countries iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
[11] Which of the following chemicals is used in photography?
A.
Aluminium hydroxide
B.
Silver bromide
C.
Potassium nitrate
D.
Sodium chloride
Ans:
Silver bromide
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Silver bromide (AgBr), a soft, pale-yellow, water insoluble salt well known (along with other silver halides) for its unusual sensitivity to light. This property has allowed silver halides to become the basis of modern photographic materials. AgBr is widely used in photographic films and is believed by some to have been used for making the Shroud of Turin. The salt can be found naturally as the mineral bromargyrite (bromyrite). Photographic properties of silver halides (in particular AgBr) were a result of deviations from an ideal crystal structure. Factors such as crystal growth, impurities, and surface defects all contribute to affect concentrations of point ionic defects and electronic traps, which subsequently affect the sensitivity to light and allow for the formation of a latent image.
[12] Fungi are plants that lack -
A.
Oxygen
B.
Carbon dioxide
C.
Chlorophyll
D.
None of these
Ans:
Chlorophyll
Explanation :
We know plants prepare their own food and so are known as autotrophs. With the help of photosynthesis they make food in which they produce glucose from carbon dioxide and sunlight.
[13] The gas which turns into liquid at the lowest temperature among the following is –
A.
hydrogen
B.
oxygen
C.
helium
D.
nitrogen
Ans:
hydrogen
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Liquid hydrogen (LH2) is the liquid state, of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below hydrogen's critical point of 33 K. However, for hydrogen to be in a full liquid state without evaporating at atmospheric pressure, it needs to be cooled to 20.28 K (-423.17 °F/-252.87°C). One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle.
[14] Gunpowder consits of a mixture of –
A.
sand and TNT
B.
TNT and charcoal
C.
nitre, sulphur and charcoal
D.
sulphur, sand and charcoal
Ans:
nitre, sulphur and charcoal
Explanation :
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpetre)— with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks.
[15] Litmus is obtained from –
A.
a bacterium
B.
a fungus
C.
an alga
D.
lichen
Ans:
lichen
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Litmus is a water-soluble mixture of different dyes extracted from lichens, especially Roccellatinctoria. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic (i.e. alkaline) conditions, with the colour change occurring over the pH range 4.5-8.3 at 25 degree C. Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly
[16] Vinegar made by fermentation from cane sugar contains –
A.
palmitic acid
B.
lactic acid
C.
citric acid
D.
acetic acid
Ans:
acetic acid
Explanation :
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient, but historically, as the most easily available mild acid, it had a great variety of industrial, medical, and domestic uses, some of which (such as a general household cleanser) are still promoted today. Commercial vinegar is produced either by fast or slow fermentation processes.
[17] Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A.
Boron
B.
Heavy water
C.
Uranium
D.
Plutonium
Ans:
Boron
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and poorly studied because the material is extremely difficult to prepare. Most studies on "boron" involve samples that contain small amounts of carbon. Chemically, boron behaves more similarly to silicon than to aluminium. Crystalline boron is chemically inert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
[18] Hydrogen bomb is based on the principle of –
A.
controlled fission reaction
B.
uncontrolled fission reaction
C.
controlled fusion reaction
D.
uncontrolled fusion reaction
Ans:
uncontrolled fusion reaction
Explanation :
A thermonuclear weapon is a nuclear weapon design that uses the heat generated by a fission bomb to compress a nuclear fusion stage which indirectly results in greatly increased energy yield (i.e., bomb "power"). It is colloquially referred to as a hydrogen bomb or H-bomb because it employs hydrogen fusion, though in most applications the majority of its destructive energy comes from uranium fission, not hydrogen fusion by itself.
[19] Rare gases are -
A.
Mono atomic
B.
di atomic
C.
tri atomic
D.
none of above
Ans:
Mono atomic
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low concentrations.
[20] Which one among the following is not a mixture?
A.
Graphite
B.
Glass
C.
Bras
D.
Steel
Ans:
Graphite
Explanation :
Graphite is a naturally-occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes.
[21] Which one of the following is found in kidney stones?
A.
Sodium oxalate
B.
Calcium oxalate
C.
Sodium chloride
D.
Calcium acetate
Ans:
Calcium oxalate
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Calcium is one component of the most common type of human kidney stones, calcium oxalate. Some studies suggest people who take supplemental calcium have a higher risk of developing kidney stones, and these findings have been used as the basis for setting the recommended daily intake for calcium in adults.
[22] Bone ash contains -
A.
Calcium sulphate
B.
Phosphoric sulphate
C.
Calcium phosphate
D.
Calcium hypophosphate
Ans:
Calcium phosphate
Explanation :
Bone ash is a. white material produced by the calcination of bones. It is primarily composed of calcium phosphate. It is commonly used in fertilizers, polishing compounds and in making ceramics such as bone china. It also has historical uses in the manufacture of baking powders and assay cupels.
[23] The hardest substance available in earth is –
A.
Platinum
B.
Silicon
C.
Diamond
D.
Gold
Ans:
Diamond
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Diamond is the hardest naturally occurring substance found on Earth. But it is not the hardest substance.
[24] A potato tuber has been cut into two halves. A few drops of iodine solution are placed on the cut surface of one of the halves. What colour change will be noticed?
A.
From brown to blue-black
B.
From brown to orange-red
C.
From blue to pink
D.
From pink to blue-green
Ans:
From brown to blue-black
Explanation :
The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.
[25] Lead pencil contains –
A.
lead
B.
ferrous sulphide
C.
lead sulphide
D.
graphite
Ans:
graphite
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.
Explanation :
Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging.