Given Mass = 400g and V = 20cm3 Density = Given Mass = 725g and V = 25cm3 Density =.
Given Mass = 131.4g and V = 18ml Density =
Given Mass = 67.7g and V = 9ml Density =

Can somebody please help me find the density.

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.

A.(nh4)(2co3)is the correct answer