The planet Gallifrey has two naturally occurring isotopes of chlorine. Chlorine-35 has an isotopic abundance of 45.89% and a mass of 34.9689 amu. Chlorine-37 has an isotopic abundance of 54.11% and a mass of 36.9659 amu.
Calculate the average atomic mass of chlorine on planet Gallifrey.

36.05 amu

Explanation:

Given data

Isotope       Mass (m)               Abundance (ab)

³⁵Cl              34.9689 amu        45.89% (0.4589)

³⁷Cl              36.9659 amu        54.11% (0.5411)

We can calculate the average atomic mass (am) of chlorine on planet Gallifrey using the following expression.

am = ∑ mi × abi

am = 34.9689 amu × 0.4589 + 36.9659 amu × 0.5411

am = 36.05 amu

if two electrons have the same n, the same ℓ, and the same ml, then they are in the same orbital. the pauli exclusion principle states that no two identical fermions (a fancy word for electrons and other subatomic particles like electrons) may occupy the same quantum state in an atom simultaneously.