Copper (ii) nitride molar mass

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.

Conservation efforts have been effective in "increasing the number of endangered species, reducing all the negative impacts of human activity, and preserving wildlife habitats".hope my answer has you : ) 

Ithink b not to sure hope that : )