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 is an example of a Chemical Change?
[A] Rusting of iron
[B] Magnetisation of iron
[C] Melting of iron
[D] Heating of iron

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2. Which among the following methods can be used to remove the permanent hardness in water due to calcium or magnesium sulphates?
[A] Sulphonate method
[B] Nitrate method
[C] Zeolite method
[D] None of these

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3. The aqueous solution of which among the following acids is called Vinegar?
[A] Oxalic acid
[B] Citric acid
[C] Acetic acid
[D] Hydrochloric acid

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4. What happens to water’s vapor pressure when heated?
[A] It increases
[B] It decreases
[C] It first increases then decreases
[D] No change

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5. What term refers to the minimum temperature at which a combustible substance begins to ignite?
[A] Fireless Temperature
[B] Ignition Temperature
[C] Static Temperature
[D] Optimum Temperature

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6. PAN (Peroxyacetyl nitrate) is a secondary gaseous compound found in _?
[A] Classical smog
[B] Volatile organic compound
[C] Photochemical smog
[D] Green manure

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7. Why most of the aromatic hydrocarbons burn with a sooty flame?
[A] Because the carbon-hydrogen ratio in aromatic compounds is high
[B] Because of the presence of the strong carbon-carbon bonds
[C] Because, hydrocarbons are unsaturated
[D] Because the carbon-hydrogen ratio in aromatic compounds is low

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8. Which of the following is the softest metal?
[A] Cesium
[B] Lead
[C] Gold
[D] Silver

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9. Which of the following chemicals is also known as "Vitriol of clay”?
[A] Aluminium sulphate
[B] Sodium silicate
[C] Zinc sulphate
[D] Copper(II) sulphate

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10. Which of the following chemicals is called Philosopher’s Wool?
[A] Brimstone
[B] Zinc oxide
[C] Magnesium hydroxide
[D] Potassium nitrate

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