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NEETChemistryStructure of Atom

Why do chromium and copper have five and ten electrons in the 3d orbitals, respectively, instead of four and nine as expected based on their position?

Options

  1. AThey violate the Aufbau principle.
  2. BThey have fully filled 4s orbitals.
  3. CThey have half-filled 4s orbitals.
  4. DFully filled and half-filled orbitals have extra stability.

Correct answer

D. Fully filled and half-filled orbitals have extra stability.

Step-by-step solution

The fully filled and half-filled orbitals have extra stability, which is why chromium and copper adopt the d5 and d10 configurations.

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