[Cotyle]

I am just at the start of my revision of chemistry at its most basic and I have bumped into something that I can't quite grasp understanding of. If any of you can assist in my attention to this it would be greatly appreciated.

I have noticed on the column numbers (those pertinent to basic revision), move through 1 - 8 indicating the valence electrons found for each atom falling beneath it. The Lewis Dot Structure displays a requirement of bonding to fill the difference that short falls the 8 needed for a "satiated" state of the outer orbital.
Example of my point; Carbon having 4 valence electrons needs an additional 4 electron bonds to acquire a state of balance, Oxygen having 6 valence electrons needs an addition 2 electron bonds for this balance.

Boron has only 3 valence electrons, This would lead me to believe that a requirement of an additional 5 electrons would be needed to balance the state of its valence shell between a formed bond covalent, ionic, hydrogen, which every is applicable. (still don't entirely understand these either)

Boron Tetra-chloride; if I understand this correctly is in a state of only 6 shared electrons.
Boron Hydride; again if I am correct, is only sharing 6 electrons to its valence shell for a stable bond.

Is there something I am missing here as to why Boron doesn't fit this rule?


If there is a huge fallacy in the way I am looking at this, Please feel free to point out the error of my ways so I can develop from them.

[Corribus]

Unfortunately, the easy rules and generalizations we learn in introductory chemistry courses do not always work, because things are usually more complicated than our approximations allow us to believe. Boron is in general an unusual element that features atypical bonding styles; actually, the chemistry and bonding of boron compounds is not completely understood and is still an area of research. Boron trihalides, for example, are electron deficient as you've noticed (explaining probably their reactivity) and the boron-halide bonds are thought to exhibit pi-bonding character - although this is debated I think. Boranes are particularly strange, featuring electron deficient 3-center-2-electron "banana bonds".

So - the unsatisfactory answer is that boron doesn't obey a lot of the simple rules you can use to understanding bonding in main group elements like carbon and oxygen.

[mafagafo]

There is another generalization you can do on this: B needs 6 electrons to become stable.

Again, this is a generalization. Some textbooks use it to simplify the problems with boron bonding. You can also assume 10 electrons for P and 12 electrons for S.

[Cotyle]

Thank you for the clarity, or lack there of it...

At least I know that I drawn to a halt in understanding due to a universal ambiguity rather than my solitary incomprehension.

Those s, p, d, and f orbitals I am still yet to find better understanding of. I thought the octet rule means that every shell of every atom required 8 electrons before another orbital was required on exterior. I have seen this isn't the case.

[vmelkon]

Those s, p, d, and f orbitals I am still yet to find better understanding of. I thought the octet rule means that every shell of every atom required 8 electrons before another orbital was required on exterior. I have seen this isn't the case.

The s, p, d, f comes from a weird naming convention that has to do with the emission spectrum.
s = sharp
p = principal
d = diffuse
f = fundamental
and the rest are just letters going from there g, h, i, j, k, l, m, n, o....

The order in which orbitals are filled is based on energy. The order isn't s < p < d < f. It can happen that d's energy is lower so it starts filling before p. In some cases, the energy level is very close and this has an effect on the chemistry. I think there was a case where the atom loses 1 electron in a chemical reaction and the other electron goes from d to p just because it is no longer paired.