VOCABULARY

particle theory of matter

heat

kinetic energy

temperature

thermal energy

thermal expansion

thermal contraction

7CHAPTER

8 Chapter 7 • Heating and Cooling NEL

Heating andCooling

KEY QUESTION: How does heat affect matter?

Looking Ahead

Heating and cooling are important in everyday natural and artifi cial processes.

The particle theory explains heating and cooling.

Heat is the transfer of energy from warmer substances to cooler substances.

Most materials expand when they are heated and contract when they are cooled.

Investigation skills can be used to learn about expansion and contraction of different materials.

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