### Homework 3.11

Posted:

**Mon Oct 30, 2017 8:37 pm**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?

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?