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.
Solids, liquids, and dense gases emit light of all wavelengths, without any gaps. We call this a continuous spectrum. Thin gases emit light of only a few wavelengths. We call this an emission or bright line spectrum. If there is a source of light behind it, a thin gas will absorb light of the same wavelengths it emits. We call this an absorption or dark line spectrum.