Question

Which of the following options does not electronic represent ground state configuration of an atom?

• A. 1s²2s²2p⁶3s²3p⁶3d⁸4s²
• B. 1s²2s²2p⁶3s²3p⁶3d⁹4s²
• C. 1s²2s²2p⁶3s²3p⁶3d¹⁰4s¹
• D. 1s²2s²2p⁶3s²3p⁶3d⁵4s¹

Answer 1

Answer:

B. 1s²2s²2p⁶3s²3p⁶3d⁹4s²

1s²2s²2p⁶3s²3p⁶3d⁹4s²

This configuration does not represent the ground state of an atom.

In the ground state, the 3d orbital should be fully filled or empty before filling the 4s orbital. The correct configuration would be:

1s²2s²2p⁶3s²3p⁶3d¹⁰4s² or 1s²2s²2p⁶3s²3p⁶4s²3d⁹

However, the given configuration 1s²2s²2p⁶3s²3p⁶3d⁹4s² represents an excited state.