In which of the following reactions does sulfur have the biggest change in oxidation…

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

Problem

In which of the following reactions does sulfur have the biggest change in oxidation number? (1)

3\text{H}_2\text{SO}_4 + 2\text{NaBr} \rightarrow 2\text{NaHSO}_4 + \text{Br}_2 + \text{SO}_2 + 2\text{H}_2\text{O}

(2)

9\text{H}_2\text{SO}_4 + 8\text{NaI} \rightarrow 8\text{NaHSO}_4 + 4\text{I}_2 + 4\text{H}_2\text{O} + \text{H}_2\text{S}

(3)

\text{H}_2\text{SO}_4 + 2\text{KMnO}_4 \rightarrow \text{K}_2\text{SO}_4 + \text{Mn}_2\text{O}_7 + \text{H}_2\text{O}

(4)

\text{H}_2\text{SO}_4 + \text{NaCl} \rightarrow \text{NaHSO}_4 + \text{HCl}