How would you calculate the formal charge of NH3?

1 Answer
Nov 5, 2015

Answer:

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.