What is the molecular shape of ammonia (NH3) according to its Lewis structure?

The molecular shape of ammonia (NH3) is trigonal pyramidal based on its Lewis structure. In the Lewis structure, nitrogen, the central atom, is bonded to three hydrogen atoms and has one lone pair of electrons. This arrangement leads to a specific geometric shape dictated by the VSEPR (Valence Shell Electron Pair Repulsion) theory, which states that electron pairs around a central atom will orient themselves to minimize repulsion.

In ammonia, the presence of the lone pair pushes the three bonded hydrogen atoms downwards, creating a three-dimensional structure that resembles a pyramid with a triangular base. The ideal bond angle in a perfect tetrahedral arrangement is about 109.5 degrees; however, the presence of the lone pair in ammonia slightly compresses the bond angles between the hydrogen atoms, resulting in angles somewhat less than 109.5 degrees. This molecular geometry is characterized by its pyramidal shape, thus confirming that ammonia is trigonal pyramidal.

The other options do not correctly describe the shape of ammonia. A tetrahedral arrangement would require four equivalent substituents, while a bent shape would imply two bonded atoms and two lone pairs. A planar shape does not fit ammonia either, as its three-dimensional structure is distinctly non-planar due