Atomic Structure — A/L Chemistry

Atoms consist of three fundamental subatomic particles: protons (positive charge), neutrons (neutral), and electrons (negative charge). The nucleus contains protons and neutrons, while electrons occupy quantized energy levels around the nucleus.

Check before you answer

1. Quantum Numbers & Electronic Configuration: Writing correct ground-state electronic configurations using s, p, d, f notation and applying the Pauli exclusion principle, Aufbau principle, and Hund's rule (especially anomalies like Cr: [Ar] 3d⁵ 4s¹ and Cu: [Ar] 3d¹⁰ 4s¹).
2. Successive Ionization Energies: Deducing the valence shell and periodic group from sharp jumps in successive ionization energy graphs.
3. Wave-Particle Duality & Line Spectra: Explaining hydrogen emission line series (Lyman, Balmer, Paschen) via electron transitions between discrete energy levels.