Hot concentrated sulphuric acid is a moderately strong oxidising agent. Which of the following reaction doe not show oxidising behaviour?
(a) Cu + 2H2SO4 CuSO4 + SO2 + 2H2O
(b) 3S + 2H2SO4 3SO2 + 2H2O
(c) C + 2H2SO4 CO2 + 2SO2 + 2H2O
(d) CaF2 + H2SO4 CaSO4 + 2HF
(d) Key Idea An oxidising agent is a species which oxidises the other species and itself gets reduced.
In reaction (iv), oxidation number of elements remains unchanged. Thus in this reaction, H2SO4 does not act as an oxidising agent.