What do you mean by magnetism? Define the paramagnetic and diamagnetic substance in detail.

Magnetism is a physical phenomenon produced by the motion of electric charge, resulting in attractive and repulsive forces between objects. It is one of the fundamental interactions of nature. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves.

Paramagnetic substances are those which are attracted by magnets and when placed in a magnetic field move from weaker to stronger parts of the field. Paramagnetism is due to the presence of unpaired electrons in the material, so all atoms with incompletely filled atomic orbitals are paramagnetic. Due to their spin, unpaired electrons have a magnetic dipole moment and act like tiny magnets. When a magnetic field is applied, these magnetic moments will tend to align with the applied field, thus reinforcing it.

Diamagnetic substances are those which are repelled by magnets and when placed in a magnetic field move from stronger to weaker parts of the field. Diamagnetism is a quantum mechanical effect that occurs in all materials; when it is the only contribution to the material's response to a magnetic field, the material is called diamagnetic. In diamagnetic materials, all the electron are paired so there is no permanent net magnetic moment per atom. Diamagnetic properties arise from the realignment of the electron paths under the influence of an external magnetic field. Most elements in the periodic table, including copper, silver, and gold, are diamagnetic.