CLUES: 1. Change in the shape, size, volume, and state of a substance.
2. Change in the composition or atomic make-up of a substance.
3. Physical change from liquid to gas or vapour.
4. Process that causes changes in a substance's composition with the
aid of fire.
5. Takes place when oxygen and moisture in the air combine with the
metal.

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.