Concept: Anomalous electronic configurations occur in transition metals to maximize stability via fully-filled (\(d^{10}\)) or half-filled (\(d^5\)) subshells.
Formula: None required.
Solution: - (i) is completely missing the \(2p\), \(4s\), and \(3d\) orbitals. It is blatantly incorrect.
- (ii) correctly shows the anomalous configuration for Copper (\(Z=29\)), where an electron is promoted to achieve a stable, fully-filled \(3d\) subshell: \( [Ar] 4s^1 3d^{10} \).
- (iii) incorrectly assigns 35 electrons to Chromium (\(Z=24\)). Its correct config is \( [Ar] 4s^1 3d^5 \).
- (iv) is the predicted (but incorrect) Aufbau configuration for Chromium.
- Hence, ONLY (ii) is correct.
Why other options are incorrect: They include structurally flawed or experimentally incorrect configurations.
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