A single electron in an orbital has quantum numbers n = 3, ℓ = 1, mℓ = 0, ms =-½. Which of the following is an acceptable set of quantum numbers for the next electron added to this orbital?

Answer 1

Each orbital can fit 2 electrons, but opposite spin direction. Therefore, the set of quantum numbers for the next electron is

n= 3, l = 1, m_l = 0 and m_s = = +1/2