Draw the Lewis Formula of an Ammonium Ion. Describe the Formation of the Ammonium Ion from Ammonia Plus H+ . Does the Hybridization of Orbitals on Nitrogen Change During the Formation of the Ammonium Ion? Do the Bond Angles Change?

The Lewis formula for an ammonium ion (NH₄⁺) can be represented as:

N
    /|

  H H

   |

  H – N – H
   |

   H

The ammonium ion is formed when ammonia (NH₃) reacts with a hydrogen ion (H⁺). In ammonia, nitrogen has three hydrogen atoms bonded to it, and it has a lone pair of electrons. When NH₃ encounters H⁺, this hydrogen ion can be accepted by the lone pair of electrons on nitrogen. This process effectively converts the lone pair into a bond, resulting in the ammonium ion.

In terms of hybridization, the nitrogen atom in ammonia initially has sp³ hybridization, as it forms three sigma bonds with hydrogen and has one lone pair. When ammonium ion is formed, nitrogen still has sp³ hybridization, since the geometry remains tetrahedral with four bonded pairs (the three hydrogen atoms and the additional hydrogen ion). Therefore, there is no change in hybridization during this transformation.

The bond angles in both molecules (NH₃ and NH₄⁺) are initially around 107° in ammonia due to the lone pair repulsion, and become closer to 109.5° in the ammonium ion because there are no lone pairs to create repulsion. Thus, the bond angles do change upon the formation of the ammonium ion.