Uncertainty Principle
It is not possible to measure simultaneously both the position and velocity (or momentum) of a microscopic particle with absolute accuracy or certainty.
Quantum Numbers
The four numbers, which are required to specify the position and energy of an electron in an atom are called quantum numbers. These are - principal quantum number (n), angular quantum number (l), magnetic quantum number (m) and spin quantum number (s). These quantum numbers combined together give a complete address of an electron in an atom.
Aufbau Principle
In the ground state of an atom, an electron enters the orbital of lowest energy first and subsequent electrons are fed in the order of increasing energies.
Pauli's Exclusion Principle
An orbital can accommodate maximum of two electrons and these two must have opposite spins.
Hund's Rule
Electron pairing will not take place in orbitals of same energy (same sub-shell) until each orbital is first singly filled with parallel spin.
Bond Order
Metallic Bond
The attractive force, which binds various metal atoms, is called metallic bond. The metallic bond is neither a covalent nor an ionic bond.
Hybridization
The phenomenon of intermixing of the orbitals of slightly different energies so as to redistribute their energies and to give a new set of orbitals of equivalent energy and shape is known as hybridization.
Hydrogen Bond
The electrostatic force of attraction, which exists between the covalently bonded hydrogen atom of one molecule and the electronegative atom of the other molecule is known as hydrogen bond.
