Question

electron affinities of N and P are extremely low​

Answer 1

Answer:

Electron affinities of N and P are low because they have 5 electrons in p subshell.So they are half filled and are pretty stable.

Answer 2

Answer:

For Phosphorus the 3p level is exactly half filled (note that half filled and fully filled orbitals are more stable configuration), so for accepting one more electron by phosphorus (that is what electron affinity is) it will diturb the stable electronic configuration and therefore the electron affinity for P is less than the N.