In acidic solution

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

Problem

In acidic solution,

\text{S}_2\text{O}_8^{2-}

is reduced to

\text{SO}_4^{2-}

. Which of the following is a correctly balanced half-reaction for this process? (a)

\text{S}_2\text{O}_8^{2-}+4\,e^-\rightarrow 2\,\text{SO}_4^{2-}

(b)

\text{S}_2\text{O}_8^{2-}+2\,e^-\rightarrow 2\,\text{SO}_4^{2-}

(c)

\text{S}_2\text{O}_8^{2-}\rightarrow 2\,\text{SO}_4^{2-}+2\,e^-

(d)

\text{S}_2\text{O}_8^{2-}+2\,\text{H}^++2\,e^-\rightarrow 2\,\text{HSO}_4^-