Hybridization of ammonia and water

The central atom on ammonia is nitrogen, which really wants to complete it's outer electron orbital---look at a periodic table) and you'll see nitrogen is three to the left of neon (a noble gas) with a complete outer orbital (s2p6) To compete the outer orbital of nitrogen (s2p3) it shares an electron with three hydrogen atoms (1s) that wants an electron to have an outer orbital be like helium (2s). The geometric shape of this s2p6 orbital of nitrogen can be interpreted as having four vertices (tetrahedral) since electrons prefer to be in pairs (their ?'spins' are opposite signs). So the nitrogen molecule is roughly tetrahedral, with hydrogen on three of the four vertices and a bare pair of electrons on the fourth vertex.

Now you dump this in water---water is kinda like ammonia, in that it also has an s2p3 formation, with hydrogen on two of the tetrahedral vertices and a bare pair of electrons on the other two. But when ammonia and water are mixed together (within reason) the ammonia molecule is in a lower degree of geometric deformation if it can add hydrogen to become a perfect tetrahedron (like methane) and water is perfectly willing to give it one. But ammonia in this case becomes a positive ion (NH4+) and water becomes a negative on (OH-).

With a surplus of OH-?'s you have a base.

The reaction is

NH3+H20 <-> NH4+ + OH-.

The <-> indicates that this is an equilibrium reaction (goes in both directions)

BTW I think what you are calling an sp3 is the same as what I am calling an s2p6, mostly because electrons orbitals normally exist as pair of electrons. Then algebraically this can be interpreted as (s2p6)/2=s2/2p6/2=s1p3=sp3. However, with the higher orbitals (d and f) this is not truly accurate.

Rap

Hi rap, sorry for being late in my reply. I'm speaking about the hybrid orbitals in both nitrogen and oxygen. It's sp3 type like methane.If we consider the drawing of an sp3 hybrid, it should be like this,

2p blank

sp3 1 1 1 1

1s 11

That means six which is true for the carbon, what about nitrogen and oxygen ? If we take nitrogen, and taking in mind that it's sp3 then it should be like the above. A tetrahedron must have four hybrid orbitals.

sorry for the electrons drawing above.

Each pole of the tetrahedron of sp3 consists of a pair of electrons with opposite spins (additional quantum #), that is what I was calling s2p6 because there are in actuality 8 electrons in the tetrahedronal field..

But yes an sp3 is an sp3 is an sp3 regardless of whether the central atom is carbon, oxygen, nitrogen, fluorine, or helium.

Rap

Thanks rap.

Hydrogen with one plus shares electron pair with NH4?


So I am trying to understand any chemistry - How does the hydrogen ion that is dissociated from water attach to the ammonia molecule and share two electrons? How does this help the H fill its valence shell? Doesn't it only need one electron?