(dissolving or reacting) . All gases are less dense than liquid water and will displace the water downwards. No good for soluble gases like ammonia, hydrogen chloride, nitrogen dioxide or sulphur dioxide. You can collect in inverted gas jar if bigger sample required.You have to watch for 'sucking back' effects. Answer   Hydrogen can be collected by the downward displacement of water because of two reasons: it is less dense than water, and so rises to the surface, and it â¦ is not very soluble in water, and so nearly all the gas can be collected because very little is dissolved in the water.
preserve - a domain that seems to be specially reserved for someone; medicine is no longer a male preserve. 1  arena, domain, sphere, orbit, area, field - a particular environment or walk of life; his social sphere is limited; it was a closed area of employment; he's out of my orbit.
Definition of remnant for English Language Learners. : 1  the part of something that is left when the other parts are gone. : 2  a small piece of cloth that is left after the rest of the cloth has been sold.