Question

(a) Number of compounds which are aromatic = $P$
(b) Number of compounds which are anti-aromatic = $Q$
(c) Number of compounds which are non-aromatic = $R$
(d) Number of compounds which readily = $S$
Undergo dimerization at room temperature
(e) Number of compound which reacts with active meal = $T$
Sum of $P+Q+R+S+T=$

Answer 1

Aromatic compound are

(a), (g), (e), (c), (h), (k)

So, $P=6$

Anti-aromatic compound are

(b), (d), (l)

So, $Q=3$

Non- aromatic compound are

(f), (i), (j)

So, $R=3$

Anti-aromatic compound can undergo dimerisation, but here only (b) & (d) will undergo dimerisation as (l) has steric hindrance because of which dimerisation do not takes place.

So, $S=2$

Anti-aromatic and Non-aromatic compound will react with active metal, but (j) will not react with active metal. Because on reaction with active metal it does not become aromatic while all other become aromatic. Thus, $T=5$

So, $P+Q+R+S+T=19$ .