Q.(i) Alcohols and phenols have higher boiling points. Why?

Alcohols and phenols boil higher than comparable hydrocarbons/ethers because their -OH groups form intermolecular hydrogen bonds; aspirin is made by acetylating salicylic acid's phenolic -OH with acetic anhydride.

1. Why alcohols and phenols have higher boiling points: the -OH group in alcohols and phenols is highly polar and can form intermolecular hydrogen bonds between the electronegative O of one molecule and the H attached to O of a neighbouring molecule. Breaking these hydrogen bonds (in addition to overcoming ordinary van der Waals forces) requires extra energy, so alcohols and phenols have significantly higher boiling points than hydrocarbons, ethers, or haloalkanes of comparable molecular mass, which cannot hydrogen-bond in this way.
2. Aspirin: aspirin is acetylsalicylic acid. It is prepared by acetylation of the phenolic -OH group of salicylic acid (2-hydroxybenzoic acid) using acetic anhydride (or acetyl chloride), typically with a trace of concentrated H2SO4 or H3PO4 as catalyst: Salicylic acid + (CH3CO)2O --(H2SO4/H3PO4)--> Aspirin (acetylsalicylic acid) + CH3COOH …