Question

Which one of the following reaction involves oxidation-reduction ?
(a) $H_2 + Br_2 \rightarrow 2HBr$
(b) $NaBr + HCl \rightarrow NaCl + HBr$
(c) $HBr + AgNO_3 \rightarrow AgBr + HNO_3$
(d) $2NaOH + H_2SO_4 \rightarrow Na_2SO_4 + 2H_2O$

Answer 1

answer should be A as hydrogen goes from 0 oxidation state to +1 and bromine goes from 0 oxidation state to -1 oxidation state