Consider the following two parallel reaction sequences starting from styrene (vinylbenzene): Sequence P: Styrene is reacted with Br ₂ in CCl ₄ , followed by treatment with excess NaNH ₂ to give the major organic product P. Sequence Q: Styrene is reacted with HBr in the presence of an organic peroxide, followed by heating with potassium tert-butoxide ( t -BuOK ) to give the major organic product Q. The total sum of el

Step-by-step solution

In Sequence P, styrene ( Ph-CH=CH ₂ ) reacts with Br ₂/ CCl ₄ to undergo electrophilic addition, forming 1,2-dibromoethylbenzene ( Ph-CH(Br)-CH ₂ Br ). Treatment of this vicinal dibromide with excess strong base NaNH ₂ causes double dehydrohalogenation, yielding phenylacetylene ( Ph-C CH ) as product P. Phenylacetylene contains a benzene ring (6 electrons) and a carbon-carbon triple bond (4 electrons), giving a total of 10 electrons. In Sequence Q, styrene reacts with HBr in the presence of peroxide to undergo anti