Question

Draw a well labelled diagram of a conductivity cell. Also write net cell reactions involved in electrolysis of aqueous NaCl.

Answer 1

Conductivity cell

Net cell reaction in electrolysis of aqueous NaCl:

The net cell reaction is the sum of two electrode reactions.

$$2\mathrm{Cl}{\phantom{A}}_{(\mathrm{aq})}^{-}⟶\mathrm{Cl}{\phantom{A}}_{2(\mathrm{g})}+2\mathrm{e}{\phantom{A}}^{-}$$	(Oxidation half reaction at anode)
$$2\mathrm{H}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_{(\mathrm{l})}+2\mathrm{e}{\phantom{A}}^{-}⟶\mathrm{H}{\phantom{A}}_{2(\mathrm{g})}+2\mathrm{OH}{\phantom{A}}_{(\mathrm{aq})}^{-}$$	(Reduction half reaction at cathode)
$$2\mathrm{Cl}{\phantom{A}}_{(\mathrm{aq})}^{-}+2\mathrm{H}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_{(\mathrm{l})}⟶\mathrm{Cl}{\phantom{A}}_{2(\mathrm{g})}+\mathrm{H}{\phantom{A}}_{2(\mathrm{g})}+2\mathrm{OH}{\phantom{A}}_{(\mathrm{aq})}^{-}$$	(Overall cell reaction)