Question

# A depolarizer used in dry cell is

A

Ammonium chloride

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

Manganese dioxide

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C

Potassium oxide

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

Sodium phosphate

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is B Manganese dioxideThe correct option is option D:The explanation for the correct option:Depolarizers are substances that are employed in primary cells to stop hydrogen gas bubbles from accumulating.A battery depolarizer always acts as an oxidizer because it absorbs electrons during the cell's discharge.A graphite rod or a metal electrode is covered in a low moisture electrolyte paste in a dry cell, which is made of a metal container. In most cases, the metal container will be made of zinc, whose base serves as a negative electrode (anode) and a positive electrode (carbon road) (cathode).Manganese dioxide and a low moisture electrolyte, such as ammonium chloride paste, that can only produce $1.5\mathrm{V}$ of voltage and is irreversible, surround it.The moistened electrolyte undergoes a reduction reaction that involves the elements manganese dioxide (${\mathrm{MnO}}_{2}$) and ammonium chloride (${\mathrm{NH}}_{4}\mathrm{Cl}$), with graphite acting as solid support for the reaction. $2{{\mathrm{NH}}_{4}}^{+}+2{\mathrm{MnO}}_{2}\to {\mathrm{Mn}}_{2}{\mathrm{O}}_{3}+2{\mathrm{NH}}_{3}+{\mathrm{H}}_{2}\mathrm{O}$An oxidation reaction takes place on the zinc container, which acts as the anode. $\mathrm{Zn}\to {\mathrm{Zn}}^{+2}+2{\mathrm{e}}^{-}$The most common dry cell is the zinc-carbon cell, commonly known as the Leclanche cell.The dry cell uses manganese dioxide as a depolarizer.Also ${\mathrm{MnO}}_{2}$ produces moisture keeping the solution moist so that ionic mobility increases.Final answer: A depolarizer used in dry cells is manganese dioxide.

Suggest Corrections
0
Explore more