# absorption spectrum of hydrogen atom [closed]

In absorption spectrum of hydrogen atom, only one electron is present in its one atom which is in ground state, so it means that all electrons can only absorb energy of photon of wavelength which lies in UV region to get to a higher energy state (by calculation it can take max wavelength =122.55nm and minimum wavelength =91.9nm).Then why do we see dark lines in its absorption spectrum in visible region also, how can it absorb energy which is in visible region to get to a higher energy state i.e. how can it absorb wavelength like 656nm? How can the photon of this wavelength make the electron to get to a higher energy state? Please explain it intuitively (using simple mathematics)?

• There is a misunderstanding in the question. Happy Sharma says that "we see dark lines in its absorption spectrum". This has no meaning. The absorption spectrum of H is made of thin bright lines, and has no dark lines. Dark lines may only be seen in continuous spectra like in the spectrum of the sun. – Maurice May 11 at 8:08
• thin bright lines are seen in emission spectrum ,in absorption spectrum there are some dark lines lines which are getting absorbed – happy sharma May 11 at 8:31
• NO ! There are no dark lines in the absorption spectrum of Hydrogen atom. – Maurice May 11 at 9:35
• By principle, absorption spectra do have dark lines, as incoming light is absorbed, if it's energy equals the transition energy between 2 energy levels. Absorption spectrum is determined by the ratio of passing and coming light intensity ( possibly modulated ). If it had bright lines, it would mean hydrogen would absorb everything but these respective energies. – Poutnik May 11 at 17:58
• @M. Farooq. You are right. I should have said "the emission spectra is made of thin bright lines". The absorption spectrum cannot be made of "bright" lines – Maurice May 11 at 18:52