Correct Option
The correct option is Sodium hydrogencarbonate : Baking soda
Explanation
Chemical compounds are frequently identified by common names derived from their historical uses, physical appearance, or industrial applications. Distinguishing between the chemical formula, systematic name, and common name is a fundamental aspect of general chemistry.
Analysis of Pairs
- (a) Sodium hydrogencarbonate : Baking soda - Correct
Sodium hydrogencarbonate ($NaHCO_3$) is commonly known as Baking soda. It is a mild, non-corrosive basic salt used in cooking to release carbon dioxide (which causes dough to rise) and in medicine as an antacid to neutralize excess stomach acid. - (b) Calcium oxide : Slaked lime - Incorrect
Calcium oxide ($CaO$) is known as Quick lime. It is obtained by the thermal decomposition of calcium carbonate (limestone). Slaked lime refers to Calcium hydroxide. - (c) Calcium hydroxide : Quick lime - Incorrect
Calcium hydroxide ($Ca(OH)_2$) is known as Slaked lime. It is produced when water is added to Quick lime ($CaO$) in a process called slaking. - (d) Zinc carbonate : Vinegar - Incorrect
Zinc carbonate ($ZnCO_3$) is chemically associated with the mineral Calamine. Vinegar is a dilute solution (approximately 5–8%) of Acetic acid (Ethanoic acid) in water, widely used as a preservative and condiment.
Key Takeaway
Baking soda is Sodium hydrogencarbonate ($NaHCO_3$). The "Lime" compounds are distinct: Quick lime is Calcium oxide ($CaO$), while Slaked lime is Calcium hydroxide ($Ca(OH)_2$). Vinegar is dilute Acetic acid.