1. Tardigrade
  2. Question
  3. Chemistry
  4. Some statement(s) about dry cell batteries are: (I). Electrolyte is a moist paste of NH 4 Cl and ZnCl 2. (II). Oxidation product is Zn 2+ and reduction product is Mn 2 O 3 (III). Anode is a zinc metal and cathode is inert graphite in a paste of MnO 2 and C -black Select the correct statement(s).

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Q. Some statement(s) about dry cell batteries are:
(I). Electrolyte is a moist paste of $NH _{4} Cl$ and $ZnCl _{2}$.
(II). Oxidation product is $Zn ^{2+}$ and reduction product is $Mn _{2} O _{3}$
(III). Anode is a zinc metal and cathode is inert graphite in a paste of $MnO _{2}$ and $C$ -black Select the correct statement(s).

Electrochemistry

Solution:

In a dry-cell (also called leclanche cell) Anode Outer cover (cylindrical) is made of zinc. Oxidation takes place at anode.

$Zn \rightarrow Zn ^{2+}+2 e ^{-}$

Cathode Graphite (carbon) rod in a paste of $MnO _{2}$ and carbon black. Electrolyte Paste of $NH _{4} Cl / ZnCl _{2}$ (with starch binder) Reduction takes place.

$2 MnO _{2}+2 NH _{4}^{+}+2 e^{-} \longrightarrow Mn _{2} O _{3}+2 NH _{3}+ H _{2} O$

Thus, I, II and III are correct.