Chemistry MCQs
Chemistry Objective (Multiple Choice) General Knowledge Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examination.
1. What is the primary event that occurs during an oxidation reaction?
[A] Electrons are gained
[B] Electrons are lost
[C] Protons are gained
[D] Protons are lost
Show Answer
Correct Answer: B [Electrons are lost]
Notes:
Oxidation is a chemical reaction in which an atom, ion, or molecule loses an electron to another substance. So, the correct answer is “Electrons are lost”. This phenomenon is often observed in various chemical and biological systems. Understanding this important process can allow us to gain insights in fields ranging from biology to materials science.
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. Consider the following:
- Cinnabar is also known as mercurblende
- The color of Cinnabar varies from dull grey to bright green
- Cinnabar is the most common source ore for refining elemental mercury
- Cinnabar is the historic source for the brilliant blue pigment termed azure
Which of the statements given above are correct?
[A] Only 1 and 3
[B] Only 2 and 4
[C] 1, 3 and 4
[D] All Four
Show Answer
Correct Answer: A [Only 1 and 3]
Notes:
Cinnabar, also known as mercurblende, is indeed the most common ore source for refining elemental mercury. However, its color range runs from scarlet to brick-red, not grey to green. It is known for providing the brilliant red or scarlet pigment known as vermilion, not a blue pigment.
4. As per Avogadro’s hypothesis , equal volumes of different gases at the same temperature and pressure contain equal number of ______?
[A] Atoms
[B] Molecules
[C] Particles
[D] Electrons
Show Answer
Correct Answer: B [Molecules]
Notes:
Avogadro’s hypothesis states that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules. This principle is foundational in chemistry, leading to the concept of the mole, which is defined as (6.022 imes 10^{23}) entities (Avogadro’s number). This means that regardless of the type of gas, if the volume, temperature, and pressure are constant, the number of molecules will be the same.
5. Which among the following minerals is also known as Horn Silver?
[A] Silver Iodide
[B] Silver Chroride
[C] Zinc Phosphate
[D] Silver Sulphide
Show Answer
Correct Answer: B [Silver Chroride]
Notes:
Chlorargyrite is the mineral form of silver chloride (AgCl). It is also known as cerargyrite and, when weathered by desert air, as horn silver. Silver chloride is formed by the disappearance of the initial silver oxide layer.
6. Plumbism is a condition which occurs due to accumulation of:
[A] Lead in the body
[B] Sodium in the body
[C] Cadmium in the body
[D] Potassium in the body
Show Answer
Correct Answer: A [ Lead in the body]
Notes:
Plumbism is also known as lead poisoning or a condition which occurs when there is accumulation of lead in body, usually over a few months' time period and even years.
7. Which of the following are the uses of Calcium carbonate?
[A] as an antacid
[B] mild abrasive in tooth paste
[C] as a filler in cosmetics
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Calcium carbonate is used as a building material in the form of marble and in the manufacture of quick lime. Calcium carbonate is also used in the manufacture of high quality paper. It finds its use as an antacid, mild abrasive in tooth paste, a constituent of chewing gum, and a filler in cosmetics.
8. Which of these compounds is also known as wood spirit?
[A] Ethanol
[B] Methanol
[C] Propanol
[D] None of the above
Show Answer
Correct Answer: B [Methanol]
Notes:
Methanol, CH3OH, also known as ‘wood spirit’. It was produced by destructive distillation of wood.
9. Which of the following metal is alloyed with pure gold to make gold ornaments?
[A] Silver
[B] Copper
[C] Zinc
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
24 carat gold is considered to be the purest form of gold but it is too soft to be made into jewellery. It is alloyed with metals like zinc, cadmium, silver or copper to make it hard.
10. In which of the following cases, components can be separated using a separating funnel?
[A] Mixture of acetone and water
[B] Mixture of oil and water
[C] Different gases in the air
[D] None of the above
Show Answer
Correct Answer: B [Mixture of oil and water]
Notes:
A separating funnel can be used to separate the components of the mixture of immiscible liquids. Components in the mixture of oil and water can be separated using this method.
