Posted: May 26, 2016 3:13 pm
ScholasticSpastic wrote:I think you're coming at the problem backwards. It's the protons that are important. The electrons are merely a means for balancing charge, and what we observe in chemistry seldom reflects what we would expect when considering each atom by itself.
I don't understand where you got the impression that the transition metals almost all have one or two valence electrons. Are you discussing shell filling conventions or the types of ions typically formed? I think some clarification is required here. Don't feel bad. Chemistry was both my favorite course and also the one where I literally cried and threw my book at the wall.
Things get wonky with the metals because the d-sub-shell electrons are very close, energetically, to the s-sub-shell electrons. Whereas with the non-metals we get to basically ignore all but the s and p sub-shells when considering valence conformations. How comfortable are you with the sub-shells? This is probably the point where you'll find clarity regarding outer shell fullness.
Well, im fine with the concept of the number of protons determining what element an atom is, and that the number of protons must equal the number of electrons. The thing is however, in the period that palladium is, all other elements have their electrons structured, so that it forms 5 (if I remember correctly, I did have a maths exam today, so my mind is still recovering) shells. Palladium however, crams the electrons into its fourth shell, even more than the other transition metals (I've read up on the transition metals being what they are, as for -some- reason they allow more electrons into a shell, putting the maximum at 18 or such).
Then as well, palladium is the ONLY element to have 18 electrons in its outermost (valence) shell.
I've not looked into sub-shells before? Is that how the blocks of the periodic table are divided then, by how the subshells work?