Potassium metal is commerically prepared by the reduction of molten KCl with metallic sodium at `850^(@)C` (1123 K). This method is based upon the following principle

Options

A. Sodium is more reactive than potassium at this temperature
B. Potassium being more volatile distils off thus shifting the reaction forward.
C. Sodium prefers to bind to chloride ions in preference to potassium ions
D. Potassium and sodium form an alloy at this temperature.

Answer

B

Explanation

`KCl(l)+Na(l)overset(1123 K (850 ^(@)C))rarrNaCl(l) + K(g)`
`{:(B.pt."of Na = "883^(@)C(1156 K)),(B.pt. "of K = "759^(@)C(1032 K)),(M.pt. "of NaCl = "600^(@)C(973 K)),(B. pt. "of KCl = "750^(@)C(1023 K)):}}"Under normal pressure"`
AT the reaction temperature only potassium is in the vapour state and as such escape out of the reaction mixture.