When concentrated sulfuric acid is poured onto solid sodium bromide, the liquid turns brown as bromine is produced - VCE - SSCE Chemistry - Question 4 - 2002 - Paper 1

In the reaction where concentrated sulfuric acid is poured onto solid sodium bromide, the sulfuric acid acts as an oxidant. This is because it facilitates the conversion of bromide ions (Br⁻) from sodium bromide to bromine (Br₂), which is evidenced by the formation of brown liquid. The oxidation reaction indicates that sulfuric acid is gaining electrons while bromide ions are losing electrons, thus classifying sulfuric acid as an oxidizing agent in this context.