Question

11. In spectroscopy elements show a pattern of bright (emission) lines that are specific to that element. For example, the lines observed when hydrogen is excited and viewed in a spectroscope are 6563 Å, 4861 Å,4340 Å, and 4102 Å. How exactly are these spectral lines produced, and what do these lines represent?

Answer 1

Every atom has electrons revolving around its nucleus. This electron does not revolve around any orbit but only in some specific orbit. The electrons has energy which depends upon the orbit in which it is travelling. Every orbit has different energy levels. When an electron jumps into an orbit with lower energy level from an orbit with higher energy level, the electron releases a photon with energy equal to difference of energies of the two orbits. The wavelength of the photons depends upon the energy and as electrons jumps from various energy levels to others it releases photons with different wavelengths.

In hydrogen atom , these wavelengths are 6563, 4861 angstrom etc.

Every atom has distinct patterns of these lines which characterises the atom. These patterns serve as the fingerprint for the atom and we can determine which atom it is by studying theses patterns.