Question

in subshells, why does an electron go to the s4 subshell before d subshell?

Answer 1

Answer:

b) in atoms of 2+ electrons, subshells increase in energy as the value of n+l increases, and for subshells of same n+l value, subshells with a lower n are lower in energy. In this example, 4s orbitals will have an energy of n+l=4 and 3d orbitals have an energy of n+l=5, that is why 4s orbitals fill before 3d orbitals.

Explanation:

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