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NEETChemistryd and f Block Elements

What is the reason for the irregular trend in the first ionization enthalpy of the metals of the 3d series?

Options

  1. AChanges in the number of s electrons
  2. BChanges in the number of p electrons
  3. CAlteration of relative energies of 4s and 3d orbitals
  4. DIncrease in the number of outer shell electrons

Correct answer

C. Alteration of relative energies of 4s and 3d orbitals

Step-by-step solution

The irregular trend in the first ionization enthalpy of the 3d series is due to the alteration of relative energies of 4s and 3d orbitals when one electron is removed.

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