Name the following organic compounds:

(i) The compound with 3 carbon atoms whose functional group is a carboxyl.

(ii) The first homologue whose general formula is C_nH_2n

(iii) The compound that reacts with acetic acid to form ethyl ethanoate.

(iv) The compound formed by complete chlorination of ethyne.

(i) Propanoic acid [C₃H₇CHO]

(ii) Ethene [C₂H₄]

(iii) Ethyl alcohol

$\underset{\text{ethyl alcohol}}{\text{C}$2\text{H}5\text{OH}} + \underset{\text{acetic acid}}{\text{CH}3\text{COOH}} \xrightarrow{\text{Conc. H}2\text{SO}4} \underset{\text{ethyl ethanoate}}{\text{CH}3-\text{COO}-\text{C}2\text{H}5} + \text{H}_2\text{O}

(iv) 1,1,2,2 tetrachloroethane