Question

Which of the following is not correct for dry cell?

• A. Zinc is used as anode
• B. Manganese is reduced from +4 to +3 state
• C. It is a primary cell
• D. $N{H}_3$ gas is liberated out

Answer 1

Answer: (D)

Ammonia produced due to reaction

$Mn{O}_2+N{H}_4^{+}+1e^{-}\to MnO(OH)+N{H}_3$

Combines with $Z{n}^{+2}$ ions to form

${\left[Zn{\left(N{H}_3\right)}_4\right]}^{2+}$