Textbook question 2A.3

[Annabella_Amato_1I]

For this question, it asks for the ground state electron configuration of As3+ (b) and Ge2+(d). I'm confused as to why the answer for b and d don't have 4p^6 considering they both have a filled 4p orbital? Thanks!

[Stuti Pradhan 2J]

Those elements themselves in the ground states do have electrons that occupy the 4p orbitals. However, since its As3+ and Ge2+, that means that 3 of the electrons have been removed from As and 2 of the electrons have been removed from Ge. The 3 electrons removed from As to get As3+ all come from the 4p orbitals as that shell is highest in energy compared to the other occupied shells, as do the 2 electrons removed from Ge to create Ge2+.

Hope this helps!

[Tatyana Bonnet 2H]

The 3+ means that the atoms are more positive, meaning they lost electrons (which are negative). Since As lost 3 e- that leaves the 4s and 3d orbital still filled as the three electrons in the p orbital were removed. The same goes for Ge with its 2 electrons removed. When removing electrons they are removed going down from highest energy to lowest energy shells, in this case from 4p first (then 4s then 3d for instance if more than 5 electrons were to be removed).