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 the following are constituents of Brass?
[A] Zinc and Copper
[B] Iron and Zinc
[C] Copper and Nickel
[D] Iron and Copper
Show Answer
Correct Answer: A [Zinc and Copper ]
Notes:
Brass is an alloy of Copper and Zinc, in proportions which can be varied to achieve varying mechanical and electrical properties. The proportions of Zinc and Copper can vary to create different types of brass alloys with varying mechanical and electrical properties.
2. Which among the following suspension in water is often called milk of magnesia because of its milk-like appearance?
[A] Magnesium Carbonate
[B] Magnesium Hydroxide
[C] Magnesium Lactate
[D] Magnesium Oxide
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Correct Answer: B [Magnesium Hydroxide]
Notes:
Magnesium Hydroxide in water is often called milk of magnesia because of its milk-like appearance. Magnesium hydroxide is the inorganic compound and occurs in nature as the mineral brucite.
3. Under standard conditions, which of the following is the most stable form of carbon?
[A] Charcoal
[B] Graphite
[C] Diamond
[D] Amorphous Carbon
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Correct Answer: B [Graphite]
Notes:
Under standard conditions, Graphite is the most stable form of carbon. It is commonly used in pencils and lubricants due to its layered structure. These layers can move over each other, making graphite soft and slippery. Besides Graphite, other forms of carbon are diamond, charcoal, and amorphous carbon, each with unique properties and applications.
4. Acid rain is capable of damaging the buildings and historic monuments which are made up of rocks such as limestone and marble. Which among the following is the end product of such reaction?
[A] Quick Lime
[B] Calcium Carbonate
[C] Calcium Hydroxide
[D] Gypsum
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Correct Answer: D [Gypsum]
Notes:
When sulfuric, and nitric acids, present in the acid rain reacts with the calcite in marble and limestone, it get dissolve and formed gypsum and washed off by the water. The rain can dissolve limestone and marble through direct contact.
5. Which of the following chemicals is also known as "sweet oil of vitriol"?
[A] Diethyl ether
[B] Aluminium sulphate
[C] Sulphuric acid
[D] Iron(III) sulphate
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Correct Answer: A [ Diethyl ether]
Notes:
Diethyl ether is a colourless, highly volatile & flammable organic compound. It was earlier used for anaesthesia but after the development of non-flammable drugs, its uses as anaesthetic has been reduced.
6. Which of the following chemicals is also known as "butter of tin"?
[A] Stannic chloride
[B] Sodium perborate
[C] Potassium nitrate
[D] Magnesium hydroxide
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Correct Answer: A [ Stannic chloride]
Notes:
“Butter of Tin” is also known as tin tetrachloride pentahydrate. It is called “butter of tin” because of its physical appearance. Its chemical formula is SnCl4*5H2O or [SnCl4 (H2O)]*3H2O.
7. Which of the following elements have a compound named as Hydrogen peroxide?
[A] Hydrogen, Carbon and Oxygen
[B] Hydrogen only
[C] Hydrogen and Oxygen
[D] Hydrogen, Oxygen and Potassium
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Correct Answer: C [Hydrogen and Oxygen]
Notes:
Hydrogen peroxide is a compound of Hydrogen and Oxygen.
8. Bell metal is an alloy of which of the following metals?
[A] Copper and Tin
[B] Copper and Mercury
[C] Copper and Lead
[D] Copper and Zinc
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Correct Answer: A [Copper and Tin]
Notes:
Bell metal is a form of bronze with a higher tin content. It is an alloy of copper and tin (typically, 78% copper, 22% tin by mass). It is used for making bells and related instruments, such as cymbals.
9. Which of the following refining methods works on the principle that impurities are more soluble in the melt than in the solid state of the metal?
[A] Liquation
[B] Electrolytic refining
[C] Zone refining
[D] Vapour Phase refining
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Correct Answer: C [Zone refining]
Notes:
Zone refining works on the principle that impurities are more soluble in the melt than in the solid state of the metal. This method is very useful for producing semiconductors.
10. Which of the following acids is used in the Lead storage battery?
[A] Hydrochloric Acid
[B] Sulphuric Acid
[C] Nitric Acid
[D] Phosphoric Acid
Show Answer
Correct Answer: B [Sulphuric Acid ]
Notes:
Lead storage battery is an example of secondary battery. It consists of a lead anode and a grid of lead packed with lead dioxide (PbO2 ) as cathode. A 38% solution of sulphuric acid is used as an electrolyte.
