Q. Sodium nitrate on reduction with Zn in presence of NaOH solution produces ${NH}_{3}.$ Mass of sodium nitrate absorbing 1 mole of electron will be
A) 7.750
B) 10.625
C) 8.000
D) 9.875
Explanation
(b)
Required equation is given below,
$Zn + 2OH^{-} \rightarrow ZnO_{2}^{2 -} + 2H^{+} + 2e^{-}$
$NO_{3}^{-} + 8H^{+} + 8e^{-} \rightarrow OH^{-} + 2H_{2}O + NH_{3}$
From the above equation
$\because$ 8 moles of electron absorbed by 85 g of $NaNO_{3}$
$\therefore$ 1 mole of electron absorbed by $\frac{85}{8}g$ of $NaNO_{3} = 10.625$ g
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.