NH2-, NH3, and NH4+ have H-N-H bond angles of 105, 107 and 109. Explain this variation in bond angles.
science - DrBob222, Tuesday, August 10, 2010 at 9:12pm
The difference lies in the number of lone pair electrons. Lone pair electrons take up more room than paired electrons; therefore, the atoms "on the other side" of the lone pair have less room and the angles are smaller. The NH4^+ has no unpaired electrons and the angle is that of a tetrahedral angle.