The difference between electron gain enthalpies will be maximum between :

The major product formed in the following reaction is

Match List I with List II

Choose the correct answer from the options given below:

Compound $$\mathrm{P}$$ is neutral, $$\mathrm{Q}$$ gives effervescence with $$\mathrm{NaHCO}_{3}$$ while $$\mathrm{R}$$ reacts with Hinsbergs reagent to give solid soluble in $$\mathrm{NaOH}$$. Compound $$\mathrm{P}$$ is