Modern chemistry relies on the Quantum Mechanical Model, which treats electrons as both particles and waves. Dual Nature of Matter (de Broglie) Everything has wave properties. The wavelength is given by: Heisenberg’s Uncertainty Principle
𝑠 ): Direction of electron spin (+1/2 or -1/2). 6. Electronic Configuration Rules The distribution of electrons follows three key principles: Aufbau Principle: Electrons fill lower-energy orbitals first. Pauli’s Exclusion Principle: No two electrons in an atom can have the same four quantum numbers. Hund’s Rule: Orbitals of equal energy are each occupied by one electron before any orbital is doubly occupied. Conclusion Understanding atomic structure allows us to predict the chemical behavior of elements and the nature of chemical bonding. From Rutherford’s nucleus to the electron clouds of quantum mechanics, our grasp of the atom continues to refine our understanding of the universe. Would you like a summary of the atomic structure class 11 notes pdf