Question

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?
(a) Cu
(b) S
(c) C
(d) Zn

Answer 1

$\boxed{(Option \: c )\: CARBON \: is \: correct }$

$\bold{REASON}$

Sulphiric acid $H_2SO_4$ is a strong oxidising agent. Its oxidation reaction involves addition of oxygen or removal of hydrogen. This property is due to the fact that $H_2SO_4$ on thermal decomposition yields nascent oxygen [O] which helps oxidation. This nascent oxygen oxidises non metals, metals, and inorganic compounds giving out sulphur dioxide.

◼$\bold{With \: copper \:( Cu)}$

Sulphuric acid reacts with copper forming copper sulphate ,water and sulphuric acid as only one gaseous product

$Cu + H_2SO_4 \longrightarrow CuSO_4 + 2H_2O + SO_2$

◼$\bold{With \: sulphur \:( S)}$

Sulphuric acid reacts with sulphur forming water and sulphur dioxide as only gaseous product and water.

$S +2 H_2SO_4 \longrightarrow 2H_2O + 3 SO_2$

◼$\bold{With \: carbon \:( C)}$

Sulphuric acid reacts with Carbon forming water and sulphuric acid and carbon dioxide as two gaseous product

$C + H_2SO_4 \longrightarrow 2H_2O + 2 SO_2 + CO_2$

◼$\bold{With \: Zinc \:( Zn)}$

Sulphuric acid reacts with Zinc forming water , zinc sulphate and sulphuric acid only one gaseous product

$Zn + H_2SO_4 \longrightarrow ZnSO_4. + 2H_2O + SO_2$

Since, only carbon gives out two gases, therefore carbon is correct.