Benzene reacts with CH3-CO-CH2-CH2-CO-Cl in the presence of anhydrous AlCl3 (Friedel-Crafts acylation) to give product P (a keto-ketone).
P on treatment with aq. NaOH and heating undergoes intramolecular aldol condensation to give a cyclic enone Q.
Molecular mass of Q =157
Percentage of oxygen in Q =15716×100=10.19%≈10%
