You are asked to burn gas using a Bunsen burner in order to boil water. Which of the following has no mass?

-- There is nothing on the list of choices that you provided that has no mass.-- There are no "things" that have no mass.  Every sample of a liquid, a gas, or a solid has mass, even if it's only an atom or two.  I think the only possible items you could name that have no mass would be spiritual, conceptual, or sensory ones, like maybe ...-- idea-- conviction-- belief-- concept-- image-- sound-- illusion-- impression-- agreement-- inclination-- tendency-- sparkle-- tingle-- painThings like that.