Give reasons: (a) Platinum, gold and silver are used to make jewellery. (b) Sodium, potassium and lithium are stored under oil. (c) Aluminium is highly reactive metal, yet it Is used to make utensils for coking. (d) Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
(a) Au, Ag and Pt are highly lustrous, malleable and ductile, so. they are used in making jewellery. (b) Na, K and Li are highly reactive matals, they react with oxygen present in air at room temperature and catches fire in presence 8foisture. They don't react with oil (kerosene), hence stored in oil. (c) Aluminium form a very protective layer of Aluminium (Al2O3) oxide on its surface which protects it from corrosion (or reaction with any food item). (d) Reduction of metal oxides to metal is cheaper and easier than the reduction of carbonate and sulphide ores. So carbonate and sulphide ores are first converted to metal oxide and then further reduced to form metals.
