Explain line spectra and its uses.

(N/A) Line spectra (atomic spectra): The emission spectra of atoms in the gas phase do not show a continuous spread of wavelength from red to violet. Instead,they emit light only at specific wavelengths with dark spaces between them. Such spectra are called line spectra or atomic spectra because the emitted radiation is identified by the appearance of bright lines in the spectra.
An emission or absorption spectrum is a photographic recording of the separated wavelengths,which is referred to as a line spectrum.
Uses: Line emission spectra are of great interest in the study of electronic structure. The characteristic lines in atomic spectra can be used in chemical analysis to identify unknown atoms. By matching the lines of the emission spectrum of the atoms of a known element with the lines from an unknown sample,one can identify the elements present. Elements like $Rb$,$Cs$,$Tl$,$In$,$Ga$,and $Sc$ were discovered when their minerals were analyzed by spectroscopic methods.