Question

Out of the following metals, which will give $H_2$ on reaction with $NaOH$?
$I:Zn$
$II:Mg$
$III:Al$
$IV:Be$

• A. $II,IV$
• B. $I,III,IV$
• C. $I,III$
• D. $I,II,III,IV$

Answer 1

Answer: (B)

$Zn,Al$ and $Be$ will give hydrogen in reaction with $NaOH$.
$Mg$ is not affected by alkalies.
$Zn+2NaOH\to N{a}_{2}Zn{O}_2\left(sodiumzincate\right)+H_2$
$2Al+2NaOH+2H_{2}O\to 2NaAl{O}_2\left(sodiummetaaluminate\right)+3H_2$
$2Al+6NaOH\stackrel{fuse}{\to }2N{a}_{3}Al{O}_3\left(sodiumaluminate\right)+3H_2$
$Be+2NaOH\to N{a}_{2}Be{O}_2+H_2$