Write a balanced equation for :

(i) Burning of ethane in plentiful supply of air.

(ii) Action of water on calcium carbide.

(iii) Heating of ethanol at 170°C in the presence of conc. sulphuric acid.

(i) Carbon dioxide and water are produced:

$2\text{C}$2\text{H}6 + 7\text{O}2[\text{excess}] \longrightarrow 4\text{CO}2 + 6\text{H}_2\text{O} + \Delta

(ii) Calcium hydroxide and ethyne are produced

$\underset{\text{calcium carbide}}{\text{CaC}$2} + \underset{\text{water}}{2\text{H}2\text{O}} \longrightarrow \underset{\text{ethyne [acetylene]}}{\text{C}2\text{H}2} + \text{Ca(OH)}_2

(iii) Ethene and water are produced

$\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}\