NH3, also known as ammonia, is a compound that consists of one nitrogen atom and three hydrogen atoms. The type of bond present in NH3 is a covalent bond.
In a covalent bond, atoms share electrons to achieve a stable electron configuration. In the case of NH3, the nitrogen atom shares its electrons with the hydrogen atoms. Nitrogen has five valence electrons, and it needs three more to complete its octet. Each hydrogen atom has one valence electron and needs one more to complete its duet. Therefore, nitrogen shares one electron with each hydrogen atom, forming three covalent bonds.
Additionally, NH3 has a lone pair of electrons on the nitrogen atom. This lone pair is not involved in bonding and gives NH3 its characteristic shape and properties. The presence of the lone pair also makes NH3 a polar molecule, as the electron density is not evenly distributed.
In summary, NH3 is held together by covalent bonds, where electrons are shared between nitrogen and hydrogen atoms, and it has a lone pair of electrons on the nitrogen atom that influences its molecular geometry and polarity.