Chemistry MCQs
Chemistry Objective (Multiple Choice) General Knowledge Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examination.
1. Which among following is also known as white gold?
[A] Nickel
[B] Rhodium
[C] Platinum
[D] Palladium
Show Answer
Correct Answer: C [Platinum]
Notes:
Platinum is a naturally white metal. It doses not need to be alloyed for color. Due to its appearance as white, it is commonly known as White Gold.
2. Which set shows copper ores as Sulfide, Carbonate, Silicate respectively?
[A] Chalcopyrite, Azurite, Dioptase
[B] Azurite, Dioptase, Chalcopyrite
[C] Dioptase, Chalcopyrite, Azurite
[D] Dioptase, Azurite, Chalcopyrite
Show Answer
Correct Answer: A [Chalcopyrite, Azurite, Dioptase]
Notes:
Chalcopyrite is a major copper sulfide ore. Azurite is a copper carbonate mineral with formula Cu₃(CO₃)₂(OH)₂. Dioptase is a copper silicate mineral with formula CuSiO₃·H₂O. These match the deposit types in sulfide, carbonate, and silicate order respectively.
3. The synthetic rubber Buna is obtained from the reaction of an unsaturated hydrocarbon with ___:
[A] Sodium
[B] Magnesium
[C] Potassium
[D] Lithium
Show Answer
Correct Answer: A [Sodium]
Notes:
Buna-S is a synthetic rubber formed by co-polymerization of a mixture of 1:3 butadiene and styrene. It is obtained from Sodium.
4. The largest component of Coal gas is__?
[A] Methane
[B] Hydrogen
[C] Carbon Dioxide
[D] Carbon Monoxide
Show Answer
Correct Answer: B [ Hydrogen]
Notes:
Typical composition of the Coal gas is as follows: •Hydrogen 50% •Methane 35% •Carbon monoxide 10% •Ethylene 5%
5. Choose the incorrect pair?
[A] Washing soda – Sodium Carbonate
[B] Caustic soda – Sodium Hydrogencarbonate
[C] Acetic acid – Ethanoic acid
[D] Bleaching powder – Calcium oxide
Show Answer
Correct Answer: D [Bleaching powder – Calcium oxide]
Notes:
Sodium carbonate is commonly known as Washing soda. Sodium Hydrogencarbonate is commonly known as Caustic soda. Ethanoic acid is commonly known as Acetic acid. calcium oxychloride is commonly known Bleaching powder.
6. Which of the following sub-atomic particle accompanies an electron emission in Beta–decay?
[A] antineutrino
[B] neutrino
[C] proton
[D] None of the above
Show Answer
Correct Answer: A [antineutrino]
Notes:
The emission of electron in β−decay is accompanied by the emission of an antineutrino (ν ) and in β+ decay, a neutrino (ν) is generated.
7. Which of the following substance was used as a moderator in CIRUS reactor?
[A] Heavy water
[B] water
[C] solid graphite
[D] No moderator was used
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Correct Answer: A [Heavy water]
Notes:
CIRUS (Canada India Research U.S.) reactor was constructed in 1960. This 40 MW reactor used natural uranium as fuel and heavy water as moderator.
8. Which of the following is an endothermic reaction?
[A] Decomposition of calcium carbonate to calcium oxide and carbon dioxide
[B] Respiration
[C] Burning of Natural gas
[D] All of the above
Show Answer
Correct Answer: A [Decomposition of calcium carbonate to calcium oxide and carbon dioxide]
Notes:
Decomposition of calcium carbonate to calcium oxide and carbon dioxide is an endothermic reaction. Respiration and Burning of Natural gas are examples of exothermic reactions.
9. What is the order of the reaction which is independent of the concentration of reactants?
[A] Zero order
[B] First order
[C] Second order
[D] Third order
Show Answer
Correct Answer: A [Zero order]
Notes:
Order of a reaction can be 0, 1, 2, 3 and even a fraction. A zero order reaction means that the rate of reaction is independent of the concentration of reactants.
10. Who gave the law of octaves for arrangement of elements?
[A] Lothar Meyer
[B] Dmitri Mendeleev
[C] John Alexander Newlands
[D] Johann Dobereiner
Show Answer
Correct Answer: C [John Alexander Newlands]
Notes:
Newland law of octaves states that If the elements are arranged in order of their increasing atomic weights, every 8th element had similar properties to the first one. It was similar as the first and eighth note in music.
