AIM: What are changes of state? What are changes of state?

AIM: What are changes of state?

What are changes of state?


Explain how thermal energy is involved in changes of state


thermal energy, thermal energy,

Evaporation, melting point, Evaporation, melting point,

freezing, vaporization, freezing, vaporization,

change of state, condensation, change of state, condensation,

phase changephase change







What happens if you leave an ice cube in a glass at room

temperature?

How can you change the water back to ice ?

What happens to the heat?


Investigate:

Have students investigate what Have students investigate what happens when they breathe on a happens when they breathe on a

mirror held at different distances.mirror held at different distances.

Why does this happen?Why does this happen?

Have students investigate what Have students investigate what happens when they breathe on a happens when they breathe on a

mirror held at different distances.mirror held at different distances.

Why does this happen?Why does this happen?


Investigate:

OBSERVE water evaporating OBSERVE water evaporating and boiling:and boiling:

How are boiling and evaporation How are boiling and evaporation different?different?

OBSERVE water evaporating OBSERVE water evaporating and boiling:and boiling:

How are boiling and evaporation How are boiling and evaporation different?different?


Investigate:

What solids melt at VERY high What solids melt at VERY high temperatures.temperatures.

What solids melt at VERY high What solids melt at VERY high temperatures.temperatures.


Particles of a substance are called Particles of a substance are called _____ ?_____ ?

MoleculesMolecules

Particles of a substance are called Particles of a substance are called _____ ?_____ ?

MoleculesMolecules


What are the three phases of What are the three phases of matter?matter?

Solid, Liquid, GasSolid, Liquid, Gas

What are the three phases of What are the three phases of matter?matter?

Solid, Liquid, GasSolid, Liquid, Gas


What is the difference in the What is the difference in the molecules of a solid, liquid, and gas?molecules of a solid, liquid, and gas?

What is the difference in the What is the difference in the molecules of a solid, liquid, and gas?molecules of a solid, liquid, and gas?


What is the state of matter?Describe the vibration of molecules!





Which particles have more heat?


Since warmer particles have more heat, which state do you think has

more energy?

Which would hurt more, hot water or cold water?


• THERMAL ENERGY is heat energy

• THERMAL ENERGY is the energy of the moving

particles of a substance.


• Thermal energy flows from warmer substance to a cooler substance

• So when you put something in the Freezer – it looses its heat

• The water does not gain cold!


Which state has more thermal energy: a gas or a solid?

When thermal energy flows from one direction to another

it is called heat


As a substance gains or looses heat,

It may change state from a

solid>liquid>gas

gas>liquid>solid


SOLID

Least thermal energy

Vibrates in a fixed position

GAS

Most thermal energy

Vibrates most

Shape of container if sealed

LIQUID

More thermal energy

Vibrates a little more

Shape of container


Changes b/t Solid & Liquid

MELTING

• solid to liquid

• As the ice gains energy – more molecules vibrate

• eventually the bonds that form the ice crystals break and the ice melts.

FREEZING

• the reverse: looses thermal energy

• The molecule move about more slowly

• Eventually the ice crystal start to form


Changes b/t Solid & Liquid

MELTING

• solid to liquid

• As the ice gains energy – more molecules vibrate

• eventually the bonds that form the ice crystals break and the ice melts.

FREEZING

• the reverse: looses thermal energy

• The molecule move about more slowly

• Eventually the ice crystal start to form

Changes between a liquid and a gas


Vaporization

EVAPORATION

• Water slowly gains energy

• Gradually converts to gas

• “sweating”

BOILING

• Water rapidly gains energy

• Quickly converts to gas

Reverse of Vaporization is called CONDENSATION


SOLID > GAS

SUBLIMATION

Dry Ice


REVIEW VOCABULARY –












Class Activity:

Worksheets Concept 12-2

AIM: What are habitats and niches?


Homework:

INTERNET QUESTIONS

Paragraph

AIM: What are habitats and niches?

Documents

AIM: What are changes of state? What are changes of state?