Which of the following is the electron configuration of an excited atom that is likely to emit a quantum of energy?

1s2 2s2 2p6 3s2
1s2 2s2 2p6 3s2 3p5
1s2 2s2 2p6 3s2 3p1
1s2 2s2 2p6 3s1 3p1

The electron configuration of an excited atom that is likely to emit a quantum of energy is 1s2 2s2 2p6 3s1 3p1.

The lowest energy configuration of electrons in an atom is usually referred to as its ground state.

Higher energy levels are referred to as excited states. The excited state of an atom s likely to emit a quantum of energy.

If we look at the configuration; 1s2 2s2 2p6 3s1 3p1, we can see that it corresponds to an excited state. A 3s electron has been promoted to the 3p level.

This configuration  is likely to emit a quantum of energy

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explanation:

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