Question

1. os full noble gas rules of electron configurations which of the following

ules\ is being violated in each electron configuration below? explain your answer for each. hunds rule, pauli exclusion principle, aufbau principle

1. ↑↓ 1s ↑↓ 2s ↑↓ 2p
2. ↑↓ 1s ↑↓ 2s ↑↓ ↑↓ ↑↓ 2p — 3s ↑↓ ↑↓ ↑ 3p
3. ↑↓ 1s ↑↓ 2s ↑↓ ↑↓ ↑↓ 2p ↑↓ 3s ↑↓ ↑↓ ↑ 3p

Explanation:

1. For 7: The Aufbau Principle is violated. According to the Aufbau Principle, electrons fill orbitals in order of increasing energy. Before filling the 2p - orbital, the 2s - orbital should be completely filled with 2 electrons with opposite spins. Here, the 2s - orbital is not fully filled while the 2p - orbital has electrons.
2. For 8: The Aufbau Principle is violated. The 3s - orbital should be filled before the 3p - orbital. In this configuration, the 3s - orbital is empty while the 3p - orbital has electrons.
3. For 9: No rule is violated. Electrons are filled in the order of 1s, 2s, 2p, 3s, and 3p following the Aufbau Principle. The 2p and 3p orbitals follow Hund's Rule (electrons occupy degenerate orbitals singly before pairing) and the Pauli - Exclusion Principle (no two electrons in an atom can have the same set of four quantum numbers).

Answer:

1. Violated rule: Aufbau Principle. Explanation: 2s not fully filled before 2p filling.
2. Violated rule: Aufbau Principle. Explanation: 3s empty while 3p has electrons.
3. Violated rule: None. Explanation: Follows all electron - filling rules.