Question

In the metallurgy of sodium by electrolysis, excess of calcium chloride is mixed with sodium chloride to:

• A. make the latter a good conductor
• B. make the latter soft
• C. generate more energy for the electrolytic cell
• D. assist liquefaction of the latter at a much lower temperature

Answer 1

The correct option is D assist liquefaction of the latter at a much lower temperature

Calcium chloride $\left(CaC{l}_2\right)$, is added to lower the melting point of the cell medium from the normal melting point of NaCl, ${804}^{\circ }C$, to around ${600}^{\circ }C$. The $Na\left(l\right)$ and $C{l}_2\left(g\right)$ produced in the electrolysis are kept from coming in contact and reforming NaCl.