The net reaction desired in acidic solution is

CHEMISTRY · Single correct · A Level · Chemistry · Oxidation, reduction and redox reactions · Oxidation, reduction and redox reactions

Problem

2\,\text{I}^- + \text{H}_2\text{O}_2 + 2\,\text{H}^+ \rightarrow \text{I}_2 + 2\,\text{H}_2\text{O}

. Which pair of balanced half-reactions, when added together, produces the net reaction above? (a) (1)

2\,\text{I}^- \rightarrow \text{I}_2+2\,e^-

(2)

\text{H}_2\text{O}_2 \rightarrow \text{O}_2+2\,\text{H}^++2\,e^-

(b) (1)

\text{I}_2+2\,e^- \rightarrow 2\,\text{I}^-

(2)

\text{H}_2\text{O}_2+2\,\text{H}^+ +2\,e^- \rightarrow 2\,\text{H}_2\text{O}

\text{I}^- \rightarrow \dfrac12\,\text{I}_2+e^-

(2)

\text{H}_2\text{O}_2+2\,\text{H}^+ +2\,e^- \rightarrow 2\,\text{H}_2\text{O}

(d) (1)

2\,\text{I}^- \rightarrow \text{I}_2+2\,e^-

(2)

\text{H}_2\text{O}_2+2\,e^- \rightarrow 2\,\text{OH}^-