Reading: Changes in Matter

Matter can change in many ways. A physical change changes the size, shape, or state of matter, but it does not create a new substance. Cutting paper, melting ice, and crushing a can are physical changes. The material is still paper, water, or metal after the change.

A chemical change creates one or more new substances with different properties. Burning wood, rusting iron, baking a cake, and mixing vinegar with baking soda are chemical changes. Chemical changes are often difficult or impossible to reverse.

Signs of a chemical change may include a new color, a new odor, bubbles or gas, a temperature change, or the formation of a solid. Some physical changes may also involve changes in color or temperature, so scientists use several clues before deciding what happened.

During any change, matter is not created or destroyed. The particles may move, spread out, or join together in new ways, but the total amount of matter remains the same.

Part 1: Check Your Understanding

____________________________

Part 2: Explain and Classify

a. A glass breaks: ____________________

b. A cake bakes: ____________________

c. Water freezes: ____________________

d. Vinegar and baking soda form bubbles: ____________________