I'm having some trouble with an assignment, based on the Gas Law.
There are 4 questions

A. Polar covalent  

Explanation:

The polarity of a bond depends on the electronegativity difference (ΔEN) between the bonded atoms.

If the electronegativity difference between the atoms is between 0.4 and 1.7, the bond is polar covalent.

For an N-H bond, ΔEN = |3.04-2.20| = 0.84

So, the bond is polar covalent.

B is wrong. A bond is ionic only if ΔEN > 1.6.

C is wrong. A bond is nonpolar only if ΔEN < 0.4.

D is wrong. N and H are not metals.