Which of the following statements are correct?

AAn aqueous solution of $BeCl X_{2}$ is acidic.
BAnhydrous $CaCl X_{2}$ is unsuitable for drying ammonia because it forms an addition compound.
CAn aqueous solution of $NaCl$ is basic.
DHeating $MgCl X_{2} \cdot 6 H X_{2} O$ does not give anhydrous $MgCl X_{2}$ because hydrolysis occurs.

Answer: A, B, D

Be X^{2 +}

is strongly hydrolysed, giving an acidic solution.

MgCl X_{2} \cdot 6 H X_{2} O

on heating loses

HCl

and gives basic chloride or oxide.

CaCl X_{2}

absorbs

NH X_{3}

to form

CaCl X_{2} \cdot 8 NH X_{3}

NaCl

is the salt of a strong acid and strong base, so its solution is neutral and the last statement is wrong.