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AP EAMCET202124 Aug 2021Evening ShiftChemistryStructure of AtomActual

In the electronic configuration of which of the given elements, Aufbau principle or (n+l) rule is violated?

Options

  1. AMn
  2. BGa
  3. CLa
  4. DPu

Correct answer

C. La

Step-by-step solution

Lanthanum has one electron in 5 d -orbital even through, it is before elements with electrons in 4 f -orbitals. It is because in La, the 4 f and 5 d electrons are so close in energy. Therefore, it violates Aufbau principle.

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