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chemistry/electron-configuration

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Electron Configuration Rules: Energy Levels & Subshells

Step through electron filling from 1s to 4p, track rule usage in real time, and compare expected vs actual configurations for Cr and Cu.

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Key Concepts

Aufbau Principle

Electrons occupy lower-energy subshells first to minimize total energy.

Pauli Exclusion Principle

Each orbital holds at most two electrons with opposite spins.

Hund's Rule

Electrons fill degenerate orbitals singly with parallel spins before pairing.

Understanding Electron Configuration Rules

**Electron Configuration** is the symbolic representation of the distribution of electrons within atomic orbitals. This systematic arrangement follows an energy hierarchy to ensure the atom reaches its most stable, ground-state configuration.

The filling sequence is governed by three fundamental laws: the **Aufbau Principle** (occupying lower-energy subshells first), the **Pauli Exclusion Principle** (limiting each orbital to two electrons with opposite spins), and **Hund's Rule** (maximizing unpaired electrons in degenerate orbitals).

Our interactive orbital box diagram tracks these transitions in real-time, providing specialized insights into transitional anomalies like **Chromium (Cr)** and **Copper (Cu)**, where subshell stability overrides standard patterns.

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