Hot conc. H2SO4 acts as moderately strong oxidising agent. It oxidises both metals and non-metals. Which of the following element is oxidised by conc. H2SO4 into two gaseous products?

1.  Cu

2.  S

3.  C

4.  Zn



Hint: Metal does not give two types of gaseous products with H2SO4

H2SO4 is a moderately strong oxidizing agent which oxidizes both metals and non-metals as shown below
Cu + 2H2SO4 (conc)  CuSO4 + SO2 + 2H2O
S+ 2H2SO4 (conc)  3SO2 + 2H2O
While carbon on oxidation with H2SO4 produces two types of oxides CO2 and SO2
C+ 2H2SO4 (conc)  CO2 + 2SO2 + 2H2O