# Co +2 electron configuration

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#### hasanein4u

##### Full Member

General question

when we have an element in the d subshell and we have to lose electrons.. do we lose electrons from the s orbital all the time? or if we can lose from the d in order to make it half filled we do so?

example: Co +2

it has 7 electrons in 3d ... so if we lose two electrons we will have half filled subshell which is favored
but I looked online and it says we always lose from the s subshell!

so even if losing from d would make it half filled we do not do... we lose from s instead
so the Co+2 electron configuration will end with 3d7 and 0 electrons in the 4s?

#### 412smb412

##### Full Member
General question

when we have an element in the d subshell and we have to lose electrons.. do we lose electrons from the s orbital all the time? or if we can lose from the d in order to make it half filled we do so?

example: Co +2

it has 7 electrons in 3d ... so if we lose two electrons we will have half filled subshell which is favored
but I looked online and it says we always lose from the s subshell!

so even if losing from d would make it half filled we do not do... we lose from s instead
so the Co+2 electron configuration will end with 3d7 and 0 electrons in the 4s?

highest shell first ...4>3>2>1
then highest energy lvl subshell ...f>d>p>s

it's all about stability. therefore for any element doesn't matter what it is or if its a transition metal etc you're going to lose electrons from highest shell first. Co 2+ will have 0 electrons in 4s b/c 4th is the highest energy lvl shell