Question

In the extraction of chlorine by electrolysis of brine ______.

Options

• oxidation of Cl^– ion to chlorine gas occurs.

• reduction of Cl^– ion to chlorine gas occurs.

• for overall reaction ∆G^Θ has negative value.

• a displacement reaction takes place.

Answer 1

In the extraction of chlorine by electrolysis of brine for overall reaction ∆G^Θ has negative value.

Explanation:

Extraction of chlorine from brine is based on the oxidation reaction of Cl^– ion.

\[\ce{2H2O (l) + 2Cl^{-} (aq) -> 2OH^{-} (aq) + H2 (g) + Cl2 (g)}\]

The ∆G^Θ for this reaction us + 422 kJ.

∆G^Θ = – nFE^Θ

E^Θ = `- (∆G^Θ)/(nF)`

= – 2.2 V