What is the molecular formula of a compound with a molecular mass of 540.0 g/mole that consists of 11.67 g of C, 1.11 g of H, 7.78 g N, and 4.44g of O?

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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.