Why is NH3 polar but CH4 non polar

Explanation:

Nitrogen has a lone pair of electrons. That would mean that NH3 is minus at the left end in this case.

 H

:N  H

H

Methane has its Hs 90 degrees (approximately apart.

    H

H  C  H

    H

The pulling forces on the methane cancel each other out. When that happens the chemical is non polar.

2b2t

explanation:

2b2t