<Li> Mercury - vapor lamps and sodium vapor lamps produce light from atoms in excited states . </Li> <Li> Flammable liquids do not burn when ignited . It is the vapor cloud above the liquid that will burn if the vapor's concentration is between the lower flammable limit (LFL) and upper flammable limit (UFL), of the flammable liquid . </Li> <Li> E-Cigarettes allow users to inhale "e-liquid" aerosol / vapor, rather than cigarette smoke . </Li> <P> Since it is in the gas phase, the amount of vapor present is quantified by the partial pressure of the gas . Also, vapors obey the barometric formula in a gravitational field, just as conventional atmospheric gases do . </P>

Gaseous part of earth where vapor is suspended