Unit 12: Integrated Science
CHAPTER 4
• A ____________ _____ _________ occurs if a material changes from one state to
another because _________ is either _________ ____ ____ or __________
___________ _______ ____.
• If we think of ice, water and steam…
Using Particle Theory to
explain change of state
• The graph below shows how the temperature of a material being heated would
change against time. To begin with the material is in its ___________
___________.
Mr. J.Agius Personal Notes
Page 1
Unit 12: Integrated Science
• A _____________ _____ __________ is an example of a _________
___________ taking place, because it is possible to return to the __________
____ ____________ _______. In other words the change is _______________ if
we were to start off with a GAS and then ________ ____ _______ to a ________
and then to a _________ we could get a graph which is a mirror image of the one
above.
Mr. J.Agius Personal Notes
Page 2
Unit 12: Integrated Science
TWO IMPORTANT POINTS
1. _____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
2. _____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
Mr. J.Agius Personal Notes
Page 3
Unit 12: Integrated Science
There are 5 changes of state
Description of
Phase Change
Term for Phase Change
Heat Movement During
Phase Change
Temperature
Change During
Phase Change
Heat goes into the solid as it
melts.
None
Heat leaves the liquid as it
freezes.
None
Heat goes into the liquid as it
vaporizes.
None
Heat leaves the gas as it
condenses.
None
Heat goes into the solid as it
sublimates.
None
Questions
Mark the correct answer.
1
Which of these is NOT matter?
A
A cloud
B
Your hair
C
Sunshine
D
The sun
Mr. J.Agius Personal Notes
Page 4
Unit 12: Integrated Science
2
During physical changes, matter always retains its
A
Size
B
Identity
C
State
D
Texture
3
When the temperature of a substance is lowered, its particles __________ .
A
Escape the attractive forces of the other particles
B
Vibrate more slowly
C
Stop vibrating completely
D
Vibrate more quickly
4
Which of the following is a state of matter?
A
Particle
B
Diffuse
C
Plasma
D
Thermal
5
What is the most common state of matter in the universe?
A
Solid
B
Liquid
C
Gas
D
plasma
6
Which of the following best describes particles in a solid?
A
Particles tightly packed together
B
No attractive forces between particles
C
Molecules slide past each other; sample takes shape of container
D
Fills whatever container it is in
Mr. J.Agius Personal Notes
Page 5
Unit 12: Integrated Science
7
According to the kinetic theory, all matter is composed of __________.
A
plasma
B
particles
C
solid material
D
waves
8
The __________ of a substance is the temperature at which a solid begins to liquefy.
A
heat of vaporization
B
heat of fusion
C
melting point
D
boiling point
9
A system that changes from a solid state to a liquid state gains energy.
A
True
B
False
10
The freezing point will always be a lower temperature than the boiling point (with constant
pressure).
A
True
B
False
11
Of gases, liquids, and solids, what is the densest state of matter?
A
Solid
B
Liquid
C
Gas
D
Plasma
Mr. J.Agius Personal Notes
Page 6
Unit 12: Integrated Science
Q1
Complete the table by writing in whether you think the substance is solid, liquid or gas.
Q2
Complete the crossword by answering the clues and filling in the boxes.
Q3
For each of the diagrams below, write down whether it is solid, liquid or gas.
Mr. J.Agius Personal Notes
Page 7
Unit 12: Integrated Science
Q4
Ice floats in water. What does this tell you about the density of ice compared to that of water?
Why is this unusual?
Q5
Complete the following sentences using the words given in the cloud.
Q1
Fill in the blanks in the heating curve using the words given in the word box.
Mr. J.Agius Personal Notes
Page 8
Unit 12: Integrated Science
12.
Crossword quiz on particle model of solids, liquids and gases.
1
2
3
5
4
6
7
8
9
10
11
12
13
14
15
16
Across:
1 the particles
moving fast
are far apart and
6 when a liquid changes to a gas fast
7 ice thawing
9 particles in a liquid are all ? up!
11 the bits of solids, liquids and gases
13 one way in which solids are
different than gases or liquids
14 the particles of a solid do this
15 the 'pattern' of particles in a solid
16 what a solid does on heating
Mr. J.Agius Personal Notes
Down:
2 the particles
it
are closest together in
3 very difficult to do with a solid
4 particles close together but they can
still move around
5a
word that means particles
spreading in liquids and gases
8 this happens when a gas is cooled to
form a liquid
10 when a liquid changes to a solid
11 caused by gas particles hitting
side of a container
the
12 must have this to check a theory?
Page 9