Zn gives (H\_2) gas with (H\_2SO\_4) and HCI but not with (H... | Chemistry | SolveeIt

Question

Zn gives $H_2$ gas with $H_2SO_4$ and HCI but not with $HNO_3$ because :-

$Zn$ act as oxidising agent when react with $HNO_3$

$HBO_3$ is weaker acid than $H_2SO_4$ & HCI

In electrochemical series Zn is placed above hydrogen

$NO^{??_{3}$ is reduced in preference to hydronium ion

Answer

$NO^{??_{3}$ is reduced in preference to hydronium ion

Explanation

Solution

Zn have lower value of $E_{cell}^*$ and easily gives oxidation. Zn is present above $H_2$ in electrochemical series. So, it liberates hydrogen gas from dilu. $HCI/H_2SO_4$ . But $HNO_3$ is an oxidising agent. The hydrogen obtained in this reaction is converted into $H_2O.$ In $HNO_3, \, NO_3^-$ ion is reduced and give $NH_4 \, NO_3, \, N_2O, \, NO \, and \, NO_2$ (based upon the concentration of $HNO_3$ ) [ $Zn + 2HNO_3 \longrightarrow Zn \, ( NO_3)_2 + 2 H] \times 4$ (Nearly 6% ) $HNO_3 + BH \longrightarrow NH_3 + 3H_2O$ $\frac{ NH_3 + HNO_2 \longrightarrow NH_4 \, NO_3}{ 4Zn + 10HNO_3 \longrightarrow 4 Zn ( NO_3)_2 + NH_4 \, NO_3 + 3H_2O}$

Chemistry Question on d -and f -Block Elements

Solution