The ammonium ion has the formula NH4+. How many electrons must be shown in the Lewis structure of the ammonium ion?
a) 4
b) 5
c) 8
d) 9
The ammonium ion has a positive charge of +1, which means it has lost one electron.
In the Lewis structure, each hydrogen atom will be bonded to the central nitrogen atom, and there will be one lone pair of electrons on the nitrogen atom.
Each bond requires 2 electrons, so the 4 bonds with hydrogen will account for 8 electrons.
Including the lone pair on nitrogen, a total of 9 electrons must be shown in the Lewis structure of the ammonium ion.
Therefore, the answer is (d) 9.