What property of conc. H₂SO₄ is made use of in each of the following cases? Give an equation for the reaction in each case:

(a) in the production of HCl gas when it reacts with a chloride,

(b) in the preparation of CO from HCOOH.

(c) as a source of hydrogen by diluting it and adding a strip of magnesium.

(d) in the preparation of sulphur dioxide by warming a mixture of conc. sulphuric acid and copper-turnings.

(e) hydrogen chloride gas is passed through concentrated sulphuric acid.

(f) it's reaction with (i) Ethanol (ii) Carbon.

(a) The property of being a non-volatile acid is used.

NaCl + H₂SO₄ [conc.] $\xrightarrow{\lt 200 \degree\text{C}}$ NaHSO₄ + HCl

(b) The property of being a dehydrating agent is used.

HCOOH $\xrightarrow{\text{Conc. H}$2\text{SO}4} CO + H₂O

(c) The acidic property is used.

Mg + H₂SO₄ [dil.] ⟶ MgSO₄ + H₂ ↑

(d) The property of being an oxidizing agent is used.

Cu + 2H₂SO₄ [conc.] ⟶ CuSO₄ + 2H₂O + SO₂ ↑

(e) The property of being a drying agent is used.

Hydrogen chloride gas is dried by passing through conc. sulphuric acid as it does not react with conc. sulphuric acid.

(f) (i) The property of being a dehydrating agent is used.

$\underset{\text{ ethyl alcohol}}{\text{C}$2\text{H}5\text{OH}} \xrightarrow[170\degree\text{C}]{\text{Conc. H}2\text{SO}4\text{[excess]}} \underset{ \text{ethene}}{\text{C}2\text{H}4} ↑ + \text{H}_2\text{O}\

(ii) The property of being an oxidizing agent is used.

C + 2H₂SO₄ [conc.] ⟶ CO₂ + 2H₂O + 2SO₂ ↑