How would you calculate the formal charge of NH3?

1 Answer
Nov 5, 2015

One Nitrogen atom = 1 x -3 (nitrogen's charge) = -3

Three hydrogen atoms = 3 x +1 (hydrogen's charge) = 3

-3 + 3 = 0 (net charge of NH_3)

Explanation:

If you refer to a periodic table you'll see columns. The elements in hydrogen's column have a +1 charge. The elements in nitrogen's column have a -3 charge.

You can determine the charge of the nitrogen column by starting with the noble gases(charge = 0) and counting down by column. Similarly the hydrogen column starts with +1 while the next column to the right is +2.

Transition metals are typically +3, although there are a few exceptions.