1 For severe stains, add 1-2 cups vinegar to the wash cycle as well. 2  To remove a rust stain from your cotton work clothes, moisten the spot with some full-strength vinegar and then rub in a bit of salt. 3  If itâs warm outdoors, let it dry in the sunlight (otherwise a sunny window will do), then toss it in the wash.
absorption spectrum - the spectrum of electromagnetic radiation that has passed through a medium that absorbed radiation of certain wavelengths. spectrum - an ordered array of the components of an emission or wave.
As the electrons fall back down, and leave the excited state, energy is re-emitted, the wavelength of which refers to the discrete lines of the emission spectrum. Note however that the emission extends over a range of frequencies, an effect called spectral line broadening.n absorption spectrum occurs when light passes through a cold, dilute gas and atoms in the gas absorb at characteristic frequencies; since the re-emitted light is unlikely to be emitted in the same direction as the absorbed photon, this gives rise to dark lines (absence of light) in the spectrum.