Concept:Molecular shape considers only the positions of atoms, not lone pairs.
Ammonia has a central nitrogen atom with one lone pair of electrons.
Explanation:The formula of ammonia is
NH3.
Nitrogen contributes five valence electrons, and each hydrogen contributes one electron.
Three bonding pairs are used to form N–H bonds.
One lone pair of electrons remains on the nitrogen atom.
These four regions of electron density repel one another and spread out tetrahedrally.
However, shape is determined by the arrangement of the three hydrogen atoms only.
The presence of the lone pair pushes the hydrogen atoms slightly closer together.
This produces a trigonal pyramidal shape, not a tetrahedral shape.
It is also not trigonal planar, octahedral, or square planar.
Answer:None of the options is correct; the actual shape of the ammonia molecule is trigonal pyramidal.