(a)
(i) Propanone to Propan-2-ol
 
 
(ii) Ethanal to 2-Hydroxypropanoic acid
 
 
 
(iii) Toluene to benzoic acid.
 
 
(b)
(i) Pentan-2-one and Pentan-3-one
 
 
By Iodoform Test
Pentan-2-one being a methyl ketone when treated with NaOI (I2/NaOH) gives yellow precipitate of iodoform but pentan-3-one does not.
 
 
(ii) Ethanal and Propanal
 
 
By Iodoform test
Ethanal containing group CH3-C=O linked to H, reacts with I2/NaOH (or NaOI) to give yellow precipitate of iodoform but propanal does not contain group CH3-C=O linked to H or C and hence does not react with I2/NaOH to give yellow precipitate.