Question

The Pauli exclusion principle applies to the following option.

• A. H
• B. H\(^+\)
• C. H\(^-\)
• D. He\(^+\)

Hint:

Pauli's exclusion principle is fundamental for understanding the electronic configuration of multi-electron atoms. It governs the maximum electron capacity of atomic orbitals.

Answer 1

The Correct Option is C

The Pauli Exclusion Principle is a fundamental concept in quantum chemistry and physics which states that no two fermions (like electrons) in a single quantum system can have identical quantum numbers. This principle is essential for explaining the electron configuration in atoms and the structure of the periodic table.

Let us examine the given options to determine which one adheres to the principle:

1. H - Hydrogen atom: Consists of one electron. As there is only one electron, the Pauli exclusion principle does not have any effect on its electron configuration as there are no other electrons with which to compare quantum numbers.
2. H⁺ - Hydrogen ion: Has lost its electron, so it has no electrons to which the principle could apply.
3. H^- - Hydride ion: Contains two electrons. According to the Pauli exclusion principle, when two electrons occupy the 1s orbital, they must have opposite spins to have different quantum numbers. Thus, the principle applies here as the two electrons must have opposite spins to be in the same orbital.
4. He⁺ - Helium ion: Has only one electron (after losing one); similar to a neutral Hydrogen atom, there are no electron pairs in a single quantum system, hence the principle does not apply here.

Hence, the correct answer is H^-, as it is the only species among the options with two electrons where the Pauli exclusion principle has to be applied to ensure the electrons occupy the same spatial orbital but with opposite spins.