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Question
State Hund’s rule of maximum multiplicity with a suitable example.
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Solution
Hund’s rule of maximum multiplicity:
- Statement: “Pairing of electrons in the orbitals belonging to the same subshell does not occur unless each orbital belonging to that subshell has got one electron each.”
- For example, according to Hund’s rule, each of the three-degenerate p-orbitals must get one electron of parallel spin before anyone of them receives the second electron of opposite spin. Therefore, the configuration of four electrons occupying p-orbitals is represented as
and not as↑↓ ↑ ↑ ↑↓ ↑↓ - As a result of Hund’s rule, the atom with fully filled and half-filled set of degenerate orbitals has extra stability.
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