Match List I with List II
| List I | List II |
| A. Sapphire | 1. Al2O3 |
| B. Sphalerite | 2. NaCN |
| C. Depressant | 3. Co |
| D. Corundum | 4. ZnS |
Answer & explanation
Correct answer: option 3
- Sapphire is a gemstone that contains Al2O3. Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium.
- Sphalerite is ore of zinc. The molecular formula of sphalerite is ZnS.
- In the concentration of Galena (PbS) ore, sodium cyanide is added as depressant for zinc sulphide (ZnS).
- Corundum is a mineral of aluminium with a molecular formula Al2O3.