Electron pair Beverage cup arrangement in the case of ammonia is portrayed by the outer electrons surrounding the nitrogen atom. The dot point arrangement for NH3 unveils that the N atom connects 1 pair of e- with each of the three hydrogen atoms, resulting in a total of 3 united pairs of electrons. The NH3 molecule adopts a trigonal pyramidal structure due to the arrangement of the valence electrons according to its Lewis dot structure. In the Lewis symbol depiction of NH3, the N atom is surrounded by three spots, each representing a pair of joined electrons with a H atom.