How is NH4+ ion formed?
Formation of Ammonium ion:
When ammonia (NH3) combines with H+ ion ,results in the formation of Ammonium ion through coordinate covalent bond.
In ammonia ,Nitrogen is a central atom having 5 electrons in its valence shell ,3 electrons are shared with 3-H atoms and 1 lone pair of electron complete the valence shell configuration .
Due to the presence of one lone pair electron (unshared electron pair) ,it is electron rich specie ( nucleophile)and can donate this electron pair to another atom(electrophile). Therefore ammonia is a donor. On the other hand ,when hydrogen atom loses its one valence shell electron results in H+ ion.
H+ is also known as proton because H+ ion having only one proton , no electron or neutron .
so to complete its valence shell ( duplet) H+ ion need two electrons .Therefore H+ is an electron acceptor(electrophile).
When the ammonia molecule combines with H+ ion by the donation of lone pair electron from N-atom (in ammonia) to H+ ion results in the formation of ammonium ion ,NH4+.
Coordinate Covalent bond is a type of covalent bond that forms when one atom donates a pair of electron(Nucleophile) to another atom (Electrophile).
Coordinate Covalent bond is also known as Dative or Dipolar Bond.
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