Where do they get quantum numbers from?what is their use?

Answer 1

The quantum numbers represent specific solutions to the Schrodinger equation. This equation is a partial differential equation, which means that is has differentials in both space and time. As you can imagine, the solutions to such an equation are very complex.Thankfully the form of the solutions for a specific quantum number only vary by an rational term. This term is the quantum number. In reality each of these solutions represents an electron orbital and we designate each orbital by its quantum numbers.

Answer 2

Remember that quantum particles are better described by probability waves. The quantum numbers essentially count the number of nodes in the wave function for whatever state the particle is in. In general, the larger the number of nodes, the higher the energy of the particle. Also, two fermions (like electrons or protons) cannot have exactly the same quantum numbers by the Pauli exclusion principle.

Answer 3

Quantum numbers are used to describe attributes of atoms at the subatomic level.

These numbers refer to the number of electrons in certain orbitols, the spin of the electrons, the 'charm' of the electrons, and other characteristics of the atom that are defining to it.

One thing that they do is provide a basis for the understanding of how some atoms combine with other atoms to share electrons and to satisfy certain conditions. When the 'sharing' of electrons between two or more atoms creates outer electron shells with full orbitols, the arrangements tend to be stable.