DIY bridging course question: i understand why certain atoms form certain cations. e.g. Na forms 1+ cations to gain the same electron structure as its closest noble gas(Neon) by losing an electron. However what about Silver ions and stuff? Is there a reason i have to know or is it just how it is? (see attached 'common additional cations')
Hi...Just going to give a little bit of an explanation of behind the formation of ions, so that it might make sense for silver.
So you will find that the formation of of both cations and anions works by the number of electrons in the valency shell (outermost shell) of an atom. Valency works according to the periodic table, so that Group I has a valency of 1, Group II has a valency of 2, Group III has a valency of 3, and so on. Thus, elements in Group I will form 1+ cations, Group II: 2+ cations, Group III: 3+ cations, and for the otherside of the table, Group VIII: -1 anion, Group VII: -2 anions, etc.
Since silver is a transitional metal (i.e. it is not in one of the 8 specified groups), it does not have a set ion that it forms. It can form both cation Ag+ and Ag 2+. However, the Ag 2+ is quite rare and only forms under certain conditions, so therefore it is most common to use the Ag+ cation when referring to the ion for silver.
Hope this helps!