Q. Consider the following pairs:
Common Name————-Chemical Name
1. Galena———– Lead Sulphide
2. Green vitriol ————–Copper sulphate
3. Plaster of Paris ——— Calcium sulphate
4. Calomel———–Mercurous Chloride
How many pairs are correctly matched?
Answer: C
Notes:
| Common Name | Chemical Compounds/Elements | Uses |
| Baking Soda | Sodium Hydrogen Carbonate or Sodium bicarbonate | It is used as an ingredient in baking. |
| Antiformin/ Bleach/ Chloride of Soda | Sodium hypochlorite | It is used on a large scale for surface purification, bleaching, odour removal and water disinfection. |
| Bleaching Powder | Calcium Oxychloride | It is used as a bleaching agent and disinfectant. |
| Blue Vitriol | Copper Sulphate | It is used to control fungus and algae. |
| Borax | Sodium tetraborate decahydrate/ Sodium Borate | It is used in laundry detergent. |
| Calomel | Mercurous chloride | It is used as a fungicide, and formerly in medicine as a purgative. |
| Carbolic Acid/ Hydroxybenzene/ Phenic Acid | Phenol | It is used as a disinfectant in household cleaners. |
| Carborundum | Silicon carbide | It is used in automotive brakes and clutches. |
| Caustic potash | Potassium hydroxide | It is used in liquid fertilizers, potassium soaps and detergents. |
| Chile Saltpetre | Sodium Nitrate | It is used for making high-strength glasses, fertilizers and explosives. |
| Chloroform | Trichloromethane | It is used as a solvent for lacquer, floor polishes and resins. |
| Cream of tartar | Potassium hydrogen tartrate/ potassium bitartrate | It is used in bakery to stabilize egg whites. |
| Dolomite | Calcium magnesium carbonate | It is used as an ingredient in the production of glass, bricks, and ceramics. |
| Dry Ice | Solid carbon dioxide | It is used to preserve food. |
| Epsom salt | Magnesium sulphate heptahydrate | It is known to relieve pain and inflammation. |
| Freon-12/CFC-12 | Dichlorodifluoromethane | It is used as a refrigerant in refrigerators and air conditioners. |
| Galena | Lead (ll) sulphide | It is also used in a green glaze applied to pottery. |
| Glauber’s Salt | Sodium sulphate decahydrate | It is used in medicine and as a dyeing agent. |
| Glycerol | Propane-1,2,3-triol | It is used in food and skin care industry. |
| Green Vitriol | Ferrous sulphate heptahydrate | It is used in sewage and water treatment, and as a pigment, fertilizer. |
| Gypsum | Calcium sulphate dihydrate | It is used to manufacture dry wall. |
Source: NCERT Class 10 and 12

