Question

1. classify each as a physical change or a chemical change. a. breaking a pencil in two b. water freezing and forming ice c. frying an egg d. burning wood e. leaves changing colors in the fall

Explanation:

• a. Breaking a pencil is a physical change as it only changes the shape and size, not the chemical composition.
• b. Water freezing is a physical change as it is a phase - change from liquid to solid without altering the chemical identity of water.
• c. Frying an egg is a chemical change as heat causes proteins in the egg to denature and new chemical substances are formed.
• d. Burning wood is a chemical change as wood reacts with oxygen to produce carbon dioxide, water vapor, and ash, involving chemical reactions.
• e. Leaves changing colors in the fall is a chemical change as pigments in the leaves break down and new chemical compounds are formed due to chemical reactions.

Answer:

a. Physical change
b. Physical change
c. Chemical change
d. Chemical change
e. Chemical change