Question

$Zn$ gives hydrogen with $H_{2}S{O}_4$ and HCl but not with $HN{O}_3$ because?

• A. Zn acts as oxidising agent when reacts with $HN{O}_3$
• B. $HN{O}_3$ is weaker acid than $H_{2}S{O}_4$ and HCl
• C. $Zn$ is above the hydrogen in electrochemical series
• D. $N{O}_3^{-}$ is reduced in preference to $H^{+}$ ion

Answer 1

The correct option is D $N{O}_3^{-}$ is reduced in preference to $H^{+}$ ion

Nitric acid is a very strong oxidising agent and hence it leads to the addition of oxygen to another substance. Thus when hydrogen is formed due to addition of nitric acid on zinc metal it oxidises hydrogen to water and thus the reaction becomes,

$Zn+4HN{O}_3\to Zn(N{O}_3{)}_2+2N{O}_2+2H_{2}O$