What are the rules for drawing molecular diagrams?

[leroyjenkens]

If I have a molecule of pb₂SO₄ for example, how would I draw that? What are the rules that tell me what attaches to what? When it's only 3 or 4 atoms, it's pretty easy to draw them, but when it's more than that, I have no clue what to do.

 

[Borek]

Never heard about such molecule -- I guess you got valence of lead wrong.

This is sulfate - and as such contains SO₄^2- anion, which is the same in all sulfates.

 

[leroyjenkens]

Never heard about such molecule -- I guess you got valence of lead wrong.

This is sulfate - and as such contains SO₄^2- anion, which is the same in all sulfates.

Maybe I got it wrong. I had a test today that required that I find out the oxidation states of each atom in a molecule. The molecules that contained Pb and S, I didn't know how to figure it out. If there's no shortcut rule that I can follow, I can just draw the molecule and find out the oxidation state of the atom in the molecule. But when the molecule is big, and contains more than one atom that there's no shortcut for, I don't know what to do. I can't draw it, because I can't figure out what atoms attach to the other atoms.

 

[Borek]

Pb is either +2 or +4. As I wrote earlier - in the case of larger molecules they are usually built of ready "blocks" - like sulfate anion, nitrate anion and so on. These have always the same composition and the same charge.