MCQ
Electron enters the sub-shell for which $(n + l)$ value is minimum. This is enunciated as
  • A
    Hund’s rule
  • Aufbau principle
  • C
    Heisenberg uncertainty principle
  • D
    Pauli’s exclusion principle

Answer

Correct option: B.
Aufbau principle
b
(b) According to the Aufbau principle electron filling minimum to higher energy level.

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