# Which of the following is not an electrophile? How is this determined?

## $N {O}_{2}^{+}$ $B {F}_{3}$ $C {H}_{2} = C {H}_{2}$ ${H}^{+}$

$N {O}_{2}^{+} \mathmr{and} {H}^{+} \text{positively charged}$ so attracted towards ngatively charged centers and hence they are charged electrophiles.
$B {F}_{3} \to$ A neutral molecule but the valence shell of its central atom B is not completely fulfilled.This electron deficiency makes it an electrophile.
$C {H}_{2} = C {H}_{2}$ is neutral molecule but it has got $\pi$-bond.So this molecule is capable of donating eletron.Hence does not act as an electrophile.