Question

Which colourless gas evolves, when \[{\rm{N}}{{\rm{H}}_{\rm{4}}}{\rm{Cl}}\] reacts with zinc in a dry cell battery?
A. \[{\rm{N}}{{\rm{H}}_{\rm{4}}}\]
B. \[{{\rm{N}}_{\rm{2}}}\]
C. \[{{\rm{H}}_{\rm{2}}}\]
D. \[{\rm{C}}{{\rm{l}}_{\rm{2}}}\]

Answer 1

Hint: The electrochemical cell defines the cell that produces electricity from the chemical reaction. A dry cell belongs to the class of electrochemical cell or we can say a battery used mostly in the portable electronic device and equipment of house. The dry cell that is used in common consists of zinc and carbon electrodes.

Complete Step by Step Solution:
Let's understand the dry cell in detail. A dry cell has electrolyte in the paste form to form immobilized electrolytes of low moisture content. This restricts the flowing of the paste and the low moisture is enough for the flowing of current.


Let's discuss a dry cell of Zinc and carbon electrodes . It Zinc -Carbon dry cell, a zinc container acts as an anode and a carbon graphite behaves as a cathode. The space between both the electrodes is filling up with manganese dioxide and an electrolyte of low moisture content consists of zinc chloride (\[{\rm{ZnC}}{{\rm{l}}_{\rm{2}}}\] ) and ammonium chloride (\[{\rm{N}}{{\rm{H}}_{\rm{4}}}{\rm{Cl}}\]).

Zinc undergoes a reaction ammonium chloride to give the following reaction.

\[{\rm{2N}}{{\rm{H}}_{\rm{4}}}{\rm{Cl}} + {\rm{Zn}} \to {\rm{2N}}{{\rm{H}}_3} + {\rm{ZnC}}{{\rm{l}}_{\rm{2}}} + {{\rm{H}}_{\rm{2}}}\]

The above reaction shows the liberation of hydrogen gas due to the reaction of zinc and ammonium chloride.
Hence, option C is right.

Note: The dry cells are of two types, primary and secondary . A primary dry cell is neither rechargeable nor reusable. For example, lithium cell, mercury cell. The recharge in a secondary cell is possible with the help of battery. One example is, nickel cadmium cell.