Question

State Pauli’s exclusion principle.

Answer 1

The Pauli exclusion principle is the quantum mechanical principle that states that two identical fermions cannot occupy the same quantum state simultaneously. In the case of electrons, it can be stated as follows: it is impossible for two electrons of a poly-electron atom to have the same values of the four quantum numbers: n, the principal quantum number, ℓ, the angular momentum quantum number, mℓ, the magnetic quantum number, and ms, the spin quantum number. For two electrons residing in the same orbital, n, ℓ, and mℓ are the same, so ms, the spin, must be different, and thus the electrons have opposite half-integer spins, 1/2 and -1/2. This principle was formulated by Austrian physicist Wolfgang Pauli in 1925 for electrons, and later extended to all fermions with his spin-statistics theorem of 1940.

Answer 2

Pauli Exclusion Principle.

The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers.

As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins......