What is the element that forms a 3+ ion with electron configuration [Ar] 3d^6?

Question

I know that [Ar] 3d^6 is Fe, but how can I find an element that forms the 3+ ion?

Thanks

Answer 1

I think some of these "what is the element that.....?" questions are confusing because it isn't clear if the question is about the ion or about the element. If this question refers to the element with Ar 3d6 then Fe is the answer and it does form 3+ ion in FeCl3 and Fe2O3. However, the way the question is worded makes me think the 3+ ion is Ar 3d6 which would make the element Ar 3d6 + 3 electrons and if those were arranged as 3d7 + 4s2 then the two 4s electrons + 1 of the 3d could be lost to give a 3+ ion which make the element Co which does have a +3 ion. But that is speculating that the intermediate stage can have 4s electrons. Perhaps the way some questions have been answered in class will give you an idea of what is and is not allowed. I hope I've not confused you even more.

Answer 2

This makes total sense. The answer in fact is Co. So one would need to think the way you described to find Co

Answer 3

Thank you for letting me know. You can apply that same reasoning then to your Ba? problem.

Answer 4

The answer is Co because i thought is Fe and it was an exam question so i got 0 for the answer. how it works is the configurations is {Ar}3d^6 and it is +3 charge you will think if +3 not cancel it the configuration will be {Ar}4S^2 3d^7 which means (Co). when we cancel for +3 we take s orbital first which is 4S and one from 3d^7 to make it 3D^6 there for {Ar}3d^6 with +3 charge.

Answer 5

Ar3d6