On a heating curve a plateau ( the flat portion) corresponds to: a change in temperature of a liquid. a change in temperature of a solid. a change in temperature of a gas. the solid being broken into smaller pieces. a change of state. Classify each of the following as a physical or chemical change. Corrosion of a piece [Choose ] of aluminum. Melting of ice. [Choose ] Pulverizing an [Choose ] aspirin. Digesting a candy [Choose ] bar. Explosion of [Choose ] nitroglycerin.