Metals and Non-metals

Metals such as sodium, magnesium, calcium, aluminium high up in the reactivity series are very reactive and cannot be obtained from their compounds by heating with carbon. This is because these metals have more affinity for oxygen than carbon. These metals are obtained by electrolytic reduction.

Metal	Method of reduction of oxide
K Na Ca Mg Al	All these metals cannot be reduced by coke or carbon monoxide. Electrolytic method is the only way to reduce these metals

Reduction by Electrolysis

This process is used for oxides of highly reactive metals that are above aluminium in the reactivity series. It is also used for reduction of aluminium oxide. Example:

Reduction Using Aluminium (Aluminothermy)

Aluminium is an expensive reducing agent. It is used for reduction of oxides of highly reactive metals. But these metals need to be below aluminium in the reactivity series. Example:

Aluminothermy is also used for welding broken iron rails.