Chemistry MCQs
Chemistry Objective (Multiple Choice) General Knowledge Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examination.
1. The term “white coal” sometimes referred to which of the following?
[A] Geothermal Electricity
[B] Wind Energy
[C] Hydroelectricity
[D] Biomass Energy
Show Answer
Correct Answer: C [Hydroelectricity]
Notes:
The term white coal was used for Hydroelectricity, particularly in Europe, because of its capability to produce more energy than any other source except coal. The term was coined by a French Engineer Aristide Bèrges.
2. Which among the following kinds of glass is used generally in making of the Bullet proof screens?
[A] Pyrex glass
[B] Jena glass
[C] Reinforced Glass
[D] Flint Glass
Show Answer
Correct Answer: C [Reinforced Glass]
Notes:
Reinforced Glass or Toughened glass or tempered glass is a kind of safety glass is used as s a component of bulletproof glass, for diving masks, and various types of plates and cookware.
3. The Helium atoms that have lost two electrons are called ________?
[A] Alpha rays
[B] Beta rays
[C] Gamma rays
[D] None of the above
Show Answer
Correct Answer: A [Alpha rays]
Notes:
Helium atoms that have lost two electrons are called alpha rays. Alpha rays are also called alpha particles or alpha radiation. Alpha particles are made up of two protons and two neutrons bound together into a particle that is identical to a helium-4 nucleus.
Alpha particles are named after the first letter in the Greek alphabet, α. They were the first nuclear radiation to be discovered.
When a helium atom loses its electrons, it is left with only the nucleus. This is called an alpha particle.
4. Which among the following is produced when we pass chlorine into slaked lime?
[A] DDT
[B] Baking Powder
[C] Bleaching Powder
[D] Gypsum
Show Answer
Correct Answer: C [ Bleaching Powder]
Notes:
Bleaching powder is made by passing Cl2 into slaked lime. Though bleaching powder is often written as Ca(OCl)2 , it is really a mixture and not a compound.
5. Which of the following element has the highest first ionization enthalpy?
[A] Magnesium
[B] Strontium
[C] Beryllium
[D] Barium
Show Answer
Correct Answer: C [Beryllium]
Notes:
The alkaline earth metals have low ionization enthalpies due to fairly large size of the atoms. Since the atomic size increases down the group, their ionization enthalpy decreases.
6. 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.
7. Which of the following elements has the largest atomic radii?
[A] Lithium
[B] Beryllium
[C] Boron
[D] Carbon
Show Answer
Correct Answer: A [Lithium]
Notes:
The atomic radius generally decreases across a period. Therefore, Lithium will have the largest atomic radii among the given elements as it is placed before others as we move from left to right in the periodic table.
8. Which is the first element in the Actinoid series?
[A] Actinium
[B] Bohrium
[C] Mendelevium
[D] Nobelium
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Correct Answer: A [Actinium]
Notes:
The actinoid series comprises of the 15 metallic chemical elements with atomic numbers from 89 to 103 starting from actinium through lawrencium.
9. What are the by-products of a hydrogen fuel cell?
[A] Water, heat and ozone
[B] Water and heat
[C] Water and ozone
[D] Heat, methane and Carbon dioxide
Show Answer
Correct Answer: B [Water and heat]
Notes:
The only by-products in a fuel cell by combining hydrogen and oxygen are water and heat. They do not emit greenhouse gases or other air pollutants.
10. Which of these polymers is formed by addition polymerization process?
[A] polyethene
[B] polypropylene
[C] PVC
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Some of the polymers formed by addition polymerization process are polyethene, example , terylene, nylon, polypropylene, polybutadiene, polyvinylchloride.
