MCQ
Select the incorrect statement for dry cell
- A$Mn$ is reduced from $Mn^{+4}$ to $Mn^{+3}$
- ✓$NH_3$ gas liberated out
- C$Zn$ is used as anode
- DPaste of $NH_4Cl$ and $ZnCl_2$ is used
✓
Answer
Correct option: B.
$NH_3$ gas liberated out
b
$Mn{O_4} + \mathop N{H_4} + {e^ - } \to MnO\left( {OH} \right) + N{H_3}$, $NH_3$ combine with $Zn^{+2}$, present in paste to form $[Zn(NH_3)_4]^{+2}$ complex ion.
$Mn{O_4} + \mathop N{H_4} + {e^ - } \to MnO\left( {OH} \right) + N{H_3}$, $NH_3$ combine with $Zn^{+2}$, present in paste to form $[Zn(NH_3)_4]^{+2}$ complex ion.
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