Question

Which of the following oxides reacts with $HCl$ and $NaOH$ ?

• A. $CaO$
• B. $ZnO$
• C. $N_{2}O_{5}$
• D. $CO_{2}$

Answer 1

Answer: (B)

$Z n O$ is an amphoteric oxide, it dissolves both in acid and alkalise to give zinc salt and zincates respectively.
$ZnO +2 HCl \rightarrow ZnCl _{2}+ H _{2} O$
$ZnO +2 NaOH \rightarrow \underset{\text { sodium }}{ Na _{2} ZnO _{2}}+ H _{2} O$