[hya_been]

I've been looking at the structure of sulphuric acid, and I don't understand how it can have that many bonds...wouldn't its valence have 12 electrons then? Does it have anything to do with SO4 having a 2- charge?  Where do polyatomic Ions gain electrons from, and how do you represent the gained ones structurally?

[Mitch]

Sulfur can exceed the octet rule.

[Yggdrasil]

Since sulfur is in the third period, it has the 3d orbitals available to accept electrons.  So, when bonding, sulfur will occasionally utilizes 2 d-orbitals to form six sp³d² orbitals, allowing it to form six covalent bonds.

[Mitch]

D-orbitals will not be involved, its actually a rather complicated explanation.

[demt]

the way I understood it, from my first year at uni, was that the higher oxidation state was attributed to the promotion of one 3p and one 3s electron each to an empty 3d orbital, giving a total of six sp3d2 hybrids which, after covalent bonding producing a compound from which sulphurs ox state is +12.

If this is NOT the case, then what is the mechanism by which sulphur achieves its +12 state? I can't see how it would achieve this state without the use of d electrons. If the explanation is too long, could someone point me in the right direction as I am interested in finding this out.