Which electron transition results in the emission of energy? a. 3p to 3s c. 2s to 2p

The electron transition that results in the emission of energy is  3p to 3s.

According to the Bohr model of the atom, energy is emitted when an electron in an atom moves from a higher to a lower energy level. The energy emitted is equal to the energy difference between the two energy levels.

The energy level 3p is higher than the energy level 3s. Therefore, when an electron moves from 3p to 3s, there is emission of energy.

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