Reaction of iso-propylbenzene with \( \mathrm{O_2} \) followed by the treatment with \( \mathrm{H_3O^+} \) forms phenol and a by-product \( P \). Reaction of \( P \) with \( 3 \) equivalents of \( \mathrm{Cl_2} \) gives compound \( Q \). Treatment of \( Q \) with \( \mathrm{Ca(OH)_2} \) produces compound \( R \) and calcium salt \( S \).
The correct statement(s) regarding \( P \), \( Q \), \( R \) and \( S \) is(are):
