Question

Sodium is made by the electrolysis of molten mixture of about 40% nacl and 60% cacl2 because

Answer 1

Sodium is made by eletrolysis of a moletn mixture of about 40% NaCl and 60% CaCl2 because  This mixture has lower melting point than NaCl.
Explanation :

Here the function of CaCl2 is to lower the operating temperature from 1080 K (melting point of NaCl ) to about 850 K.
NaCl ----> Na⁺+ Cl⁻
Reactions at Cathode: Na⁺ + e -> Na

At anode : 2Cl⁻ -----> Cl₂+2e
Chlorine is the by product in this process.

Answer 2

this mixture has a lower melting point than Nacl