Ethan is observing chemical and physical properties of a substance. He heats a

Question

substance and observes that the substance turns from a brown solid to a black
powder. He refers to several chemistry journals that claim this represents a chemical
reaction. From his observation and research, he concludes that the substance goes through a chemical change when heated. How can Ethan best defend his conclusion? (1 point)
by verifying that the substance is made up of only one type of element
by demonstrating that the substance will eventually melt if the temperature continues to increase
by demonstrating that the substance is less dense after it is heated
by verifying that the substance is now made up of different molecules than before it was heated