Bell Work1. What happens to the particles in a liquid as a liquid

turns into a solid?

2. What are the differences between a liquid and a gas?

3. Which states of matter have a definite shape? Which have a definite volume? Which have a definite mass?

MatterLesson 2:

Changes in State

Changes in State• changing the thermal energy of a substance results in

changing the kinetic energy of its particles

• if KE changes enough, the state of matter will change

• increasing thermal energy, increases kinetic energy

• decreasing thermal energy, decreases kinetic energy• increasing thermal energy, increases kinetic energy

Changes in State• changing the thermal energy of a substance results in

changing the kinetic energy of its particles

• if KE changes enough, the state of matter will change

Changes in State

liquid

solid gas

mel

ting

Changes in State

liquid

solid gas

mel

ting

vaporization

• two types:

• evaporation: vaporization only at the surface of a liquid

• boiling: vaporization below and at the surface of a liquid

Changes in State

liquid

solid gas

mel

ting

vaporization

condensation

Changes in State

liquid

solid gas

mel

ting

vaporization

condensation

freez

ing

Changes in State

liquid

solid gas

mel

ting

vaporization

condensation

freez

ing

sublimation

• sublimation happens when something that is normally a gas is frozen into a solid

• the difference between its freezing point and the current temp. is so great that it instantly turns to gas

Practice1. Why is changing the state of matter considered a

physical change instead of a chemical change?

2. How does thermal energy affect the kinetic energy of the particles within a substance?

3. How does kinetic energy determine state of matter?

4. Starting from a solid, what changes occur as thermal energy is increased?

5. What happens to particles as a substance condenses?

6. What is vaporization, and how are its types different?

7. What is sublimation, and what causes it to happen?