Question

HCl was passed through a solution of $CaCl_2$,$MgCl_2$ and $NaCl$. Which of the following compound(s) crystallise(s)?

• A. Both $MgCl_2$ and $CaCl_2$
• B. Only $NaCl$
• C. Only $MgCl_2$
• D. $NaCl$, $MgCl_2$ and $CaCl_2$

Answer 1

Answer: (B)

Only $NaCl$

Answer 2

On passing $HCl$ through aqueous solution of $CaCl_2, MgCl_2$ and $NaCl$, crystals of pure $NaCl$ seperate out. Calcium and magnesium chloride being more soluble than $NaCl$, remain in solution.