So for each of the coordination complexes, figure out what oxidation state the central metal ion is in. from there, determine number of electrons in outer orbital.
[Cr(H2O)6](ClO3)2 -> Chlorate ion is -1, so Cr(H2O)6 is +2, or Cr+2
Chromium has an electron config of [Ar] 3d5 4s1, and with 2 less electrons, the electron configuration should be [Ar] 3d4 . for transition metals, iirc, the highest s orbital is highest energy/outermost and will be taken from first.
I believe LFT deals with the order of filling d orbitals only (iirc) and therefore you shouldnt have to worry about it.
for ruthenium, make sure when counting d electrons that you count both 3d and 4d if required to
This post was edited by cialda on Apr 1 2014 09:27pm