A gaseous substance is an object (such as steam) that has the propeties of a gas. The properties of a gas. Steam is an example-the particles are widely spread throughout the … substance and have plenty of room to move about. Gas is, in simpler terms, a fluid with no shape, volume of mass.hemist for uranium nuclear fuels. Examples at standard conditions: carbon dioxide, sulfur dioxide, nitrogen dioxide, methane, propane, hydrofluoric acid, hydrochloric acid, ammonia, etc.