Question

which q.ns are different for the last two electrons placed in oxygen?
i
m₁
mₛ
i and mₛ
m₁ and mₛ

Explanation:

• The electronic configuration of oxygen (\(O\)) is \(1s^{2}2s^{2}2p^{4}\).
• The last two electrons are in the \(2p\) orbital.
• For electrons in the same orbital (\(n\) and \(l\) are the same), the magnetic quantum number (\(m_{l}\)) can be the same (as electrons can be in the same \(p\) - orbital orientation in some cases, but here for the last two electrons in \(2p\) of \(O\), they are in different \(p\) - orbitals so \(m_{l}\) is different) and the spin quantum number (\(m_{s}\)) is different (as per Pauli's exclusion principle, electrons in the same atom cannot have the same set of four quantum numbers. Since \(n = 2\), \(l=1\) for both, if \(m_{l}\) is different (as they are in different \(p\) - orbitals) and \(m_{s}\) is also different (\(+\frac{1}{2}\) and \(-\frac{1}{2}\))).

Answer:

\(m_{l}\) and \(m_{s}\)