How many of the following reactions will yield a ketone as one of the major organic products? (i) Ozonolysis of 2,3-dimethylbut-2-ene followed by reaction with Zn/H₂O (ii) Reaction of benzene with acetyl chloride in the presence of anhydrous AlCl₃ (iii) Oxidation of butan-2-ol with CrO₃ (iv) Oxidation of toluene with alkaline KMnO₄ followed by heating (v) Ozonolysis of propene followed by reaction with Zn/H₂O

Step-by-step solution

(i) Ozonolysis of 2,3-dimethylbut-2-ene followed by Zn/H₂O (reductive ozonolysis) yields two molecules of propanone (acetone), which is a ketone. (ii) Benzene reacts with acetyl chloride in the presence of anhydrous AlCl₃ (Friedel-Crafts acylation) to yield acetophenone, which is a ketone. (iii) Oxidation of butan-2-ol (a secondary alcohol) with CrO₃ yields butan-2-one, which is a ketone. (iv) Oxidation of toluene with alkaline KMnO₄ and heat yields potassium benzoate, which is a salt of a carboxylic acid, not a ke