Chemistry Class 11 Chapter: 2. Structure of Atom | Page 11

Quantum mechanics is based on a fundamental equation which is called Schrodinger equation .
Schrodinger ’ s equation : For a system ( such as an atom or a molecule whose energy does not change with time ) the Schrödinger equation is written as :
H ψ = E ψ
When Schrödinger equation is solved for hydrogen atom , the solution gives the possible energy levels the electron can occupy and the corresponding wave function ( s ) of the electron associated with each energy level . Out of the possible values , only certain solutions are permitted . Each permitted solution is highly significant as it corresponds to a definite energy state . Thus , we can say that energy is quantized .
ψ gives us the amplitude of wave . The value of ψ has no physical significance . Ψ 2 gives us the region in which the probability of finding an electron is maximum . It is called probability density .
Orbital : The region of space around the nucleus where the probability offinding an electron is maximum is called an orbital .
Quantum numbers : There are a set of four quantum numbers which specify the energy , size , shape and orientation of an orbital . To specify an orbital only three quantum numbers are required while to specify an electron all four quantum numbers are required .