Answer:
n: 1, ℓ: 0, ml: 0, ms:+1/2
n: 1, ℓ: 0, ml: 0, ms:-1/2
n: 2, ℓ: 0, ml: 0, ms:+1/2
n: 2, ℓ: 0, ml: 0, ms:-1/2
Explanation:
Beryllium has 4 electrons and its electron configuration is 1s² 2s².
The principal quantum number (n) describes the level of energy. Then, the first two electrons have n = 1, and the second 2 electrons have n = 2.
The azimuthal number (ℓ) describes the subshell of energy. All the 4 electrons are in s subshells, which correspond to ℓ = 0.
The magnetic quantum number (ml) describes the orbital of the subshell. The s subshell has only 1 s orbital, so the only possible value for ml is 0.
The spin quantum number (ms) describes the spin of the electron and can take 2 values: +1/2 or -1/2.
Considering these rules, the quantum numbers for these 4 electrons are:
n: 1, ℓ: 0, ml: 0, ms:+1/2
n: 1, ℓ: 0, ml: 0, ms:-1/2
n: 2, ℓ: 0, ml: 0, ms:+1/2
n: 2, ℓ: 0, ml: 0, ms:-1/2