(a)
Electrophiles are the species having a tendency to accept a pair of electron, $e.g.,$ $NO_{2}^{+},Br^{+}$ etc.
Nucleophiles are the species having a tendency to donate a pair of electron. $e.g.,$ $CH_{3}OH.N_{3}^{-}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.