Students recognize that a particular color change is a characteristic property of a substance and that a color change can also be used as evidence that a chemical reaction has occurred ... conclude ...

Chemical reactions make new chemicals. Atoms are rearranged during a chemical reaction, but the number of atoms does not change. Evidence of chemical reactions includes a large temperature change ...

Every chemical reaction involves a change in energy because different substances hold different amounts of energy. During the reaction, bonds inside the substances that are reacting together must ...

If they collide with enough energy, bonds can break and new bonds can form in a chemical reaction. The reactants just sit there until energy is added with the flame. The added energy is enough to make ...