Question

question 3
1 pts
which statement gives the name and correct principle which is used to determine the
arrangement of electrons in degenerate orbitals when writing electron configurations?
hunds rule: put one electron in each degenerate orbital first, then add one more electron with an
opposite spin to each orbital.
aufbau principle: fill all degenerate orbitals first, then fill in any higher or lower energy orbitals which
are not degenerate.
mendeleev: leave unoccupied spaces in the degenerate orbitals in case we discover any new orbitals.
pauli principle: only put one electron in any orbital.
question 4
1 pts
what is a set of correct quantum numbers (n, i, m) for the last electron of p?
2,1,1
3,2,0
3,0,0
3,1,1

Explanation:

Question 3

• Hund's rule states that electrons occupy degenerate orbitals (orbitals of the same energy) singly first with parallel spins before pairing up.
• The Aufbau principle is about filling orbitals in order of increasing energy (not specifically about degenerate orbitals).
• Mendeleev is related to the periodic table, not electron - orbital filling rules.
• The Pauli Exclusion Principle states that no two electrons in an atom can have the same set of four quantum numbers (not about degenerate orbital filling as described in the question).

• Phosphorus (\(P\)) has an atomic number of \(15\). The \(P^{-}\) ion has \(16\) electrons.
• The electron configuration of \(P^{-}\) is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}\). The last electron is in a \(3p\) orbital.
• For a \(3p\) orbital:
• The principal quantum number \(n = 3\) (since it is in the third shell).
• For a \(p\) orbital, the angular momentum quantum number \(l=1\).
• The magnetic quantum number \(m_{l}\) can be \(- 1,0,1\).

Answer:

Hund's rule: put one electron in each degenerate orbital first, then add one more electron with an opposite spin to each orbital.

Question 4