Pauli’s exclusion principle: No two electrons in an atom can have the same value for the same set of four quantum numbers. Thus if two electrons have identical values of n ℓ and m it follows from this principle that they must differ in their spins i.e., +½ or -½. This means that two electrons
De Broglie’s theory of wave nature of electrons: Electron, like light has dual character (particle and wave like) de Broglie suggested the wave nature of electrons and derived the relation λ = h/p where λ is the wavelength and p the momentum of the electron and h is Plank’s constant. This relation is verified by
Nature of light and electromagnetic spectrum: According to Newton’s corpuscular theory, light is propagated as a stream of particles, called corpuscles. This could justify the phenomenon of reflection and refraction of light but failed to explain the phenomenon of diffraction, interference etc. Clerk Maxwell suggested that light waves are associated with both electric and magnetic