The answer is 19 ahhahaha
Electronic configuration of cromium is
Cr-[Ar]4s¹3d⁵
When cromium loses two electrons it becomes Cr⁺².
So its electronic configuration becomes,
Cr⁺²-[Ar]3d⁴
One electron will go from 4s orbital and one electron will go from 3d orbital.
So the answer here is D. [Ar]3d⁴ -because after losing 2 electrons electronic configuration of cromium becomes [Ar] 3d⁴.
Your answer is C. its level of dissolved minerals ~A
The blueprint process
The best known is a process using ammonium ferric citrate and potassium . The paper is impregnated with a solution of ammonium ferric citr