Explain the process by which the metal is obtained from its molten chloride

The highly reactive metals like K,Na,Ca, and Mg are extracted by the electrolysis of their molten chloride.
for example:
Extraction of sodium metal:
Sodium metal is extracted by the electrolytic reduction of molten chloride.
when electric current is passed through molten sodium chloride , it decomposes to form sodium and chlorine gas.
2NaCl(l)-----------------> 2Na +Cl2 (gas).