in a chemical equation, which symbol should be used to indicate that a substance is in solution?; which symbol can be used to indicate the pressure at which a chemical reaction is carried out?; which equation has both a liquid and a gas as products?; the compound co2 is made of; which formula equation shows a reversible reaction?; which formula equation represents the burning of sulfur to produce sulfur dioxide?; which statement best describes the formula equation cl2(g) + 2kbr(aq) right arrow. 2kcl(aq)+ br2(l)?; which word equation shows hydrogen reacting with oxygen to form water?