Ante Assignment
1 How may you carry out Chemical
qualitative analysis for four samples of salt A .B. C Suspected to contain chloride ion, Carbonate lon, nitrate lon
Sulfate ion​

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

C. chemical changeshope i : )