(a) (i) When aldol condensation is carried out between two different aldehydes and/or ketones, it is called cross aldol condensation.
(ii) Sodium salt of carboxylic acids on heating with soda lime lose carbon dioxide and form hydrocarbons. This reaction is called decarboxylation.
(b) (i) Pentan-2-one when treated with NaOI (I2 /NaOH) gives yellow precipitate of iodoform but pentan-3-one does not give this test.
(ii) Benzaldehyde being an aldehyde gives silver mirror with Tollen’s reagent but acetophenone being a ketone does not give this test.
(iii) Benzoic acid produces brisk effervescence with sodium bicarbonate solution while phenol does not.