Question

refer to the orbital diagram image below. choose the best option that matches each description. no term will be used more than once. 4 points
(a) 1s² 2s² 2p⁴ 3s² 3p⁴ 4s² 3d²
(b) 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸
(c) 1s² 2s² 2p⁶ 3s² 3p⁴
(d) 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d⁸
(e) 1s² 2s² 2p⁶ 3s² 3p⁶
a b c d e
an atom with 6 valence electrons
violates the rules of filling electrons in orbitals
violates the rules of energy levels

Explanation:

1. For an atom with 6 valence - electrons: Valence electrons are in the outermost shell. We count the electrons in the highest - energy sub - shells. In option (C), the outer shell electrons are in \(3s^23p^4\), and \(2 + 4=6\).
2. For violates the rules of filling electrons in orbitals: According to Hund's rule, electrons fill degenerate orbitals singly first before pairing up. In option (A), in the \(3p\) sub - shell, electrons are paired up before all orbitals are singly occupied, violating Hund's rule.
3. For violates the rules of energy levels: Electrons fill orbitals in order of increasing energy (\(1s<2s<2p<3s<3p<4s<3d\)). In option (D), the \(4s\) orbital is not fully filled before electrons start filling the \(3d\) orbital, violating the Aufbau principle.

Answer:

An atom with 6 valence electrons: C
Violates the rules of filling electrons in orbitals: A
Violates the rules of energy levels: D