Question

Which of the following is an electrophilic reagent?

• A. $H_{2}O$
• B. $O{H}^{-}$
• C. $N{O}_2^{+}$
• D. $C{l}^{-}$

Answer 1

Answer: (C)

$N{O}_2^{+}$

Water has 2 lone pairs on oxygen, so it is a nucleophile.
$O{H}^{-}$ ion has 3 lone pairs on oxygen, again a nucleophile.
$C{l}^{-}$ ion has 4 lone pairs on chlorine, so it is a nucleophile.
$N{O}_2^{+}$ is a positively charged species and lacks electrons, so it is an electrophile.