Free Chemistry in Daily Life MCQs with Answers

211. The metal, which is a constituent of vitamin B12 is____________?

• A. Iron
• B. Magnesium
• C. Zinc
• D. Cobalt

Explanation: Vitamin B12 contains cobalt at the centre of its corrin ring, which is why it is also called cobalamin. Iron is found in haemoglobin, not in the structure of vitamin B12.

212. Which Gas is included in Fry Chips Packets for safety?

• A. Nitrogen gas
• B. Carbon dioxide
• C. Oxygen
• D. Hydrogen

Explanation: Nitrogen is used because it is largely inert and displaces oxygen inside the packet, slowing oxidation and spoilage of the chips. Carbon dioxide can also be used in some food packaging, but nitrogen is the standard gas for fried-chip packets.

213. Enology is the study of____________?

• A. Wine
• B. Digestion
• C. Kidneys
• D. None

Explanation: Enology, or oenology, is the scientific study and production of wine. The other options refer to unrelated biological subjects.

214. Which metal is added to steel to make it stainless steel?

• A. Chromium
• B. Aluminium
• C. Carbon
• D. Copper

Explanation: Chromium forms a thin, self-repairing oxide layer on steel, protecting it from rust and corrosion. Aluminium can also resist corrosion, but it is not the defining addition in stainless steel.

215. What is the common name for the drug acetyl salicylic acid?

• A. Paracetamol
• B. Analgin
• C. Aspirin
• D. Penicillin

Explanation: Acetylsalicylic acid is the chemical name of aspirin, a drug used chiefly for pain, fever and inflammation. Paracetamol and analgin are different analgesic medicines, while penicillin is an antibiotic.

216. Which natural element has the highest melting point?

• A. Iron
• B. Tungsten
• C. Copper
• D. Silver

Explanation: Tungsten has the highest melting point among the listed elements, about 3,422°C, which is why it has been used in high-temperature applications. Iron, copper and silver melt at much lower temperatures.

217. At what temperature does silver melt?

• A. 275 °C
• B. 327 °C
• C. 961.8 °C
• D. 100 °C

Explanation: Silver melts at about 961.8 °C, because its metallic lattice requires a high temperature to break down. The lower values listed correspond roughly to other substances, not silver.

218. The reaction between methane and chlorine in diffused sunlight is__________?

• A. Oxidation
• B. Reduction
• C. Polymerisation
• D. Radical substitution

Explanation: In diffused sunlight, chlorine forms radicals that replace hydrogen atoms in methane, producing chloromethane and hydrogen chloride. This is therefore a free-radical substitution reaction rather than oxidation, reduction or polymerisation.

219. The term PVC used in the plastic industry stands for______________?

• A. Phosphavinyl chloride
• B. Phosphor vanadiu chloride
• C. Polyvinyl chloride
• D. Polyvinyl carbobate

Explanation: PVC stands for polyvinyl chloride, a plastic polymer made from vinyl chloride units. The other expansions are not recognised chemical names for this material.

220. Oil of vitriol is_________?

• A. Nitric acid
• B. Hydrochloric acid
• C. Phosphoric acid
• D. Sulfuric acid

Explanation: Oil of vitriol is the old name for sulfuric acid, H₂SO₄, reflecting its oily appearance and highly corrosive nature. Nitric and hydrochloric acids have different traditional names and chemical compositions.