Question: 58: Match List-I with List-II :
| List – I (Compounds) | List – II (Molecular Formula) |
|---|---|
| (a) Borax | (i) \mathrm{NaBO}_{2} |
| (b) Kernite | (ii) \mathrm{Na}_{2}\mathrm{B}_{4}\mathrm{O}_{7}\cdot4\mathrm{H}_{2}\mathrm{O} |
| (c) Orthoboric acid | (iii) \mathrm{H}_{3}\mathrm{BO}_{3} |
| (d) Borax bead | \mathrm{Na}_{2}\mathrm{B}_{4}\mathrm{O}_{7}\cdot10\mathrm{H}_{2}\mathrm{O} |
Choose the correct answer from the options given below :
(1) (a) – (iv), (b) – (ii), (c) – (iii), (d) – (i)
(2) (a) – (ii), (b) – (iv), (c) – (iii), (d) – (i)
(3) (a) – (iii), (b) – (i), (c) – (iv), (d) – (ii)
(4) (a) – (i), (b) – (iii), (c) – (iv), (d) – (ii)
Answer: Option (1)
Explanation:
Borax is sodium tetraborate decahydrate. Its molecular formula is \mathrm{Na}_{2}\mathrm{B}_{4}\mathrm{O}_{7}\cdot10\mathrm{H}_{2}\mathrm{O},
so (a) matches with (iv).
Kernite is sodium tetraborate tetrahydrate. Its molecular formula is \mathrm{Na}_{2}\mathrm{B}_{4}\mathrm{O}_{7}\cdot4\mathrm{H}_{2}\mathrm{O},
so (b) matches with (ii).
Orthoboric acid has the molecular formula \mathrm{H}_{3}\mathrm{BO}_{3},
so (c) matches with (iii).
Borax bead is sodium metaborate formed during the borax bead test.
Its molecular formula is \mathrm{NaBO}_{2}, so (d) matches with (i).
Thus, the correct matching is (a)-(iv), (b)-(ii), (c)-(iii), and (d)-(i).