Free Chemistry in Daily Life MCQs with Answers

61. The only non metal exists in liquid state is ___________?

• A. Mercury
• B. Bromine
• C. Phosphorus
• D. Iodine

Explanation: Bromine is the only non-metal that is liquid at ordinary room temperature. Mercury is also liquid, but it is a metal.

62. Chlorophyll contains _____metal.

• A. Iron
• B. Calcium
• C. Magnesium
• D. Potassium

Explanation: The centre of a chlorophyll molecule contains magnesium, which helps it absorb light energy for photosynthesis. Iron is central to haemoglobin, a commonly confused comparison.

63. Metal are highly ___________ ?

• A. Electropositive
• B. Electronegativity
• C. Both of these
• D. Neutral

Explanation: Metals readily lose electrons to form positive ions, so they are described as electropositive. Electronegativity refers to an atom’s tendency to attract electrons in a bond, a property generally stronger in non-metals.

64. Which medicine can be used to make urine red in colour?

• A. isoniazir
• B. iron capsule
• C. Rifampicin
• D. Omeprazole

Explanation: Rifampicin can turn urine, sweat, tears, and other body fluids orange-red because of its strongly coloured metabolites. This harmless colour change is a characteristic effect of the medicine.

65. 1 Carat is equal to __________?

• A. 0.2 g
• B. 0.3 g
• C. 0.4 g
• D. 0.5 g

Explanation: A carat is a unit of mass used for gemstones and equals 200 milligrams, or 0.2 grams. It should not be confused with karat, which measures the purity of gold.

66. Pure limestone is called _______?

• A. Aluminum Oxide
• B. Calcium Carbonate
• C. Calcium Sulphate
• D. None of these

Explanation: Pure limestone is calcium carbonate, CaCO₃, the same chemical compound found in chalk and marble in different forms. Calcium sulphate is associated with gypsum, not limestone.

67. Potassium nitrate is used in__________?

• A. Medicine
• B. Fertilizer
• C. Salt
• D. Glass

Explanation: Potassium nitrate is widely used as a nitrogen-potassium fertilizer because it supplies both nutrients needed for plant growth. It also has other uses, but fertilizer is the standard answer among these options.

68. The chemical name of chalk is

• A. Sodium nitrate
• B. Zinc sulfate
• C. Sulphuric acid
• D. Calcium carbonate

Explanation: Chalk is mainly calcium carbonate, CaCO₃, formed from compacted microscopic shells or other calcium-rich material. The other choices are different chemical substances, including an acid and salts.

69. What is the name of that system, which uses radioactivity to decide the period of materials of-pre-historic period ?

• A. Radium dating
• B. Uranium dating
• C. Carbon dating
• D. Deuterium dating

Explanation: Carbon dating estimates the age of once-living material by measuring the remaining radioactive carbon-14 and comparing it with its known decay rate. It is useful for archaeological materials within a limited age range.

70. Milk tastes sour when kept in the open for sometime due to the formation of __________?

• A. lactic acid
• B. citric acid
• C. acetic acid
• D. carbonic acid

Explanation: Bacteria convert milk sugar, lactose, into lactic acid when milk is left exposed, lowering its pH and producing the sour taste. Acetic acid is associated more with vinegar production.