Homework 3.11

[Isaac Eyler 1E]

3.11

Question: Which M^3+ ions (where M is a metal) are predicted to have the following ground-state electron configurations:
(a) [Ar] 3d^6
(b) [Ar] 3d^5

The solutions manual says:
(a) Co^3+
(b) Fe^3+

To find this, do you simply add 3 electrons to the given ionized configuration (i.e.: [Ar] 3d^6), first by filling the s orbital (with 2 electrons) and then by filling the d orbital with the remaining one? Is this a proper way to approach this problem?

[sahiltelang-Discussion 1J]

Yes, this is the way to complete these problems but you have to keep in mind about the exceptions in the column starting with chromium and the column starting with copper as they only have one in the s, thus you would be taking two off the d.

[Daniel Rivas 3L]

Yeah that's the way you do it I think. And it also works the same way for 3.9. But 3.9 is easier since it asks for M^2+ ions and that means you put them in the s shell only.