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Pauli Exclusion Principle

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What is Pauli Exclusion Principle?

The Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers (n, l, mₗ, mₛ). As a consequence, each atomic orbital can hold at most two electrons, and they must have opposite spins (spin-up and spin-down). This principle, proposed by Wolfgang Pauli in 1925, is fundamental to understanding electron configurations and the periodic table.

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Term Pauli Exclusion Principle

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The Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers (n, l, mₗ, mₛ). As a consequence, each atomic orbital can hold at most two electrons, and they must have opposite spins (spin-up and spin-down). This principle, proposed by Wolfgang Pauli in 1925, is fundamental to understanding electron configurations and the periodic table.

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