Match the substances in column A with their chemical names in column B. Column…
2024
Match the substances in column A with their chemical names in column B.
Column (A) Column (B)
(a) Slaked lime (i) Calcium oxide
(b) Table salt (ii) Sodium bicarbonate
(c) Limestone (iii) Calcium carbonate
(d) Caustic soda (iv) Calcium hydroxide
(e) Quick lime (v) Sodium hydroxide
(f) Baking soda (vi) Sodium chloride
- A.
(a)-(iv), (b)-(vi), (c)-(iii), (d)-(v), (e)-(i), (f)-(ii)
- B.
(a)-(vi), (b)-(ii), (c)-(v), (d)-(i), (e)-(iii), (f)-(iv)
- C.
(a)-(i), (b)-(vi), (c)-(iii), (d)-(v), (e)-(ii), (f)-(iv)
- D.
(a)-(iv), (b)-(v), (c)-(iii), (d)-(ii), (e)-(i), (f)-(vi)
Show answer & explanation
Correct answer: A
Everyday chemicals are usually known by a common (trivial) name, while chemistry identifies the same substance by a systematic name tied directly to its composition. This question tests whether each common name is matched to the correct chemical identity among calcium compounds (oxide, hydroxide, carbonate) and sodium compounds (chloride, hydroxide, bicarbonate).
Common name | Chemical name | Formula |
|---|---|---|
Slaked lime | Calcium hydroxide | Ca(OH)2 |
Quick lime | Calcium oxide | CaO |
Limestone | Calcium carbonate | CaCO3 |
Table salt | Sodium chloride | NaCl |
Caustic soda | Sodium hydroxide | NaOH |
Baking soda | Sodium bicarbonate | NaHCO3 |
Matching each identity above to columns (a)-(f) gives: (a) Slaked lime pairs with (iv) Calcium hydroxide; (b) Table salt pairs with (vi) Sodium chloride; (c) Limestone pairs with (iii) Calcium carbonate; (d) Caustic soda pairs with (v) Sodium hydroxide; (e) Quick lime pairs with (i) Calcium oxide; and (f) Baking soda pairs with (ii) Sodium bicarbonate.
Cross-checking with a related reaction confirms the two lime compounds are distinct: quick lime (CaO) reacting with water forms slaked lime (Ca(OH)2), so the two are related but not interchangeable. Likewise, baking soda (NaHCO3) and caustic soda (NaOH) are both sodium compounds but are chemically distinct — one a mild bicarbonate used in cooking, the other a strong alkali used industrially. Every one of the six pairs above is internally consistent with the substances’ actual formulas.
The complete sequence (a)-(iv), (b)-(vi), (c)-(iii), (d)-(v), (e)-(i), (f)-(ii) is therefore the set that matches every substance to its correct chemical identity.