(i) Compound X is Ethanol (C₂H₅OH).
Structure:
$$\text{H} - \overset{|}{\underset{|}{\text{C}}} - \overset{|}{\underset{|}{\text{C}}} - \text{O} - \text{H}$$
(Full structural formula: CH₃–CH₂–OH, with each carbon having appropriate H atoms)
(ii) When ethanol is heated with excess concentrated H₂SO₄ at 443 K, dehydration occurs and ethene is produced.
$$\text{CH}_3\text{CH}_2\text{OH} \xrightarrow{\text{conc. H}_2\text{SO}_4,\ 443\text{ K}} \text{CH}_2\text{=CH}_2 + \text{H}_2\text{O}$$
Role of conc. H₂SO₄: It acts as a dehydrating agent — it removes water from ethanol to form ethene.
(iii) The hydrocarbon produced is Ethene (C₂H₄). It is an unsaturated hydrocarbon (alkene).
Electron dot structure of ethene:
$$\text{H} : \overset{..}{\text{C}} :: \overset{..}{\text{C}} : \text{H}$$
Each carbon shares a double bond (4 electrons) with the other carbon and a single bond with each hydrogen atom.
---