CHE 121 Name:
Chapter 1 practice
1. Identify the following as physical or chemical changes:
a. Boiling water
b. Burning a candle
c. Melting chocolate
d. Baking cookies
e. Digesting food
2. Label each example below is a pure substance or a mixture. If a mixture, specify hetero- or homogeneous.
a. Concrete blocks
b. A human being
c. Copper wire
d. The air in this room
e. Distilled water
f. Sea water
