This document discusses the properties of matter. It defines matter as anything that takes up space and has mass. Matter exists in three states: solid, liquid, and gas. Each state has distinct properties related to how the particles are arranged and how they move. Solids have a fixed shape and particles that vibrate in place. Liquids take the shape of their container as particles move around each other. Gases spread out and particles move quickly in any direction. The document also discusses phase changes as matter changes between solid, liquid, and gas states due to heating and cooling. Other topics covered include diffusion, surface tension, and material properties.

1. Physics
Form two
Chapter one
Properties of matter
Prepared: Farah khadaad

2. Properties of Matter
Particular nature of matter
Look around the classroom everything, from the clothes you are wearing to air you breath
is matter , matter is very important matter makes up everything including living things like
plants and people , it also makes non-living things such as tables and chairs
Things as big as an elephant or as tiny as a grain of sand on a beach are matter
Matter: is everything that it takes up space and has mass
Everything is matter and matter comes in three different states
 Solid
 Liquid
 And gas
That means that everything is either a solid, a liquid or a gas
Each state has properties
Properties of solids
 Solid don’t change shape easily
Thing of a piece of paper you can change its shape by crumpling it, but
it does not change its shape by itself, you have to use your energy to
make the shape change.
If you put a solid in a container it would not change its shape
 Solid particles do not move around
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3.  Solid particles are in an aligned array look at the pictures (notice) the particles are lined
up in tight row, they can’t move.
Property of solid Why they are like this
They have a fixed shape and
cannot flow
The particles cannot move from place to
place
They cannot be compressed or
squashed
The particles are close together and
have no space to move into
Properties of liquids
 Liquids take the shape of their container, if you pour milk into a glass it will take the
shape of the glass, if you pour the milk into a bowl it takes the shape of the bowl.
 Liquids have surface tension, the particles hold on to each other, like holding hands with
a friend, the surface of a glass filled with water holds together because the particles
hold one to each other that is called surface tension.
 Liquids move around; the particles in liquids are farther apart than
these of solids so they can move around more, that’s why liquids
take the shape of their container.
Properties of liquids Why they are like this
They flow and take the shape of their
container
The particles can move around each
other
They cannot compressed or squashed The particles are close together and
have no space to move into
Properties of gases
 Gas is invisible that means you can’t see it, the particles are so
far apart they are invisible, but they are still there! Thing about
oxygen, you can’t see it, but you know it’s there because you
breath it
 Gas particles move around freely; they are spread out move
fast, like when you are running on the playground at recess.
Properties of gas Why they are like this
They flow and completely fill their
container
The particles can move quickly in all
direction
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4. They can be compressed or squashed The particles are far apart and have space
to move into
Challenge questions
1. What is the matter?
2. State two different between solids and gases
3. Think about a can of soda all three states of matter are there
a. What part is solid matter?
b. What part is liquid matter?
c. What part is gas matter
4. What about you? All three states of matter are a part of you
a. Name a part of you that is solid?
b. Name a part of you that is liquid?
c. Name a part of you that is gas?
5. A basketball has only two states of matter, what two states of matter are in a
basketball?
6. Which Statement is True?
A. Liquids have a definite shape and volume
B. States of matter are defined by the substances they are made up of
C. Gases have a definite shape and volume
D. Solids have a definite shape and volume
7. Draw a diagram of
A. Gas particles
B. Liquid particles
C. Solid particles
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5. Kinetic theory of matter
The kinetic particle theory explains the properties of the different states of matter. The
particles in solids, liquids and gases have different amounts of energy. They are arranged
differently and move in different ways this is called” kinetic theory of matter”
This table summarizes the arrangement and movement of the particles in solids, liquids and
gases, and shows simple diagrams of the arrangement of the particles that you should be able
to recognize.
Summery
Solid Liquids gas
Arrangement of particles Close
together
regular
pattern
Close
together
random
Far part
Movement of particles Vibrate
about a
fixed
position
Move
around
each other
Move quickly an
any direction
Diagram
 The particles in solids, liquids and gases have different amount of energy, in gases the
particles have most energy and are moving around at high speed, particles in solids are
fixed and can only vibrates they have less energy than the particles in liquids which are free
to move.
 As the temperature increases the size of the vibrations or the speed of the particles
increases the particles are taken up more space and substance expands
 When the temperature decreases the particles have less energy, in a solid they vibrate less
and so take up less space the solid contract.
 In liquids and gases the particles also have less energy, and move more slowly the gas or
liquid becomes denser as the temperature decrease.
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6. Phase Change
As you know, if you heat a block of ice, it won’t simply get warmer. It will also melt and become
liquid. If you heat it even further, it will boil and become a gas. When a substance changes
between being a solid, liquid, or gas, we say it has undergone a phase change.
Melting
When a solid is heated, the particles are given more energy and start to vibrate faster. At a
certain temperature, the particles vibrate so much that their ordered structure breaks down. At
this point the solid melts into liquid. The temperature at which this change from solid to liquid
happens is called the melting point. Each solid has a set melting point at normal air pressure. At
lower air pressure, such as up a mountain, the melting point lowers
• Melting point - SPECIFIC temperature when melting occurs
• Each pure substance has a SPECIFIC melting point.
Substance Melting point °C
Water 0°C
Nitrogen -210°C
Sodium 98°C
Common salt 801°C
Silver 962°C
Carbon 3500 °C
Freezing
Lava is liquid rock, which erupts through a volcano at temperatures as high as 1,500ºC (2,732ºF)
through a volcano. However, the red-hot lava cools as it meets the Earth’s surface, and turns
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7. back into solid rock again. This change from liquid to solid is called freezing or solidifying. It is
the opposite process to melting.
Boiling
When a liquid is heated, the particles are given more energy. They start to move faster and
further apart. At a certain temperature, the particles break free of one another and the liquid
turns to gas. This is the boiling point. The boiling point of a substance is always the same; it
does not vary
• Boiling Point: is temperature at which a liquid boils
• Each pure substance has a SPECIFIC boiling point
Substance Boiling point oC
Water 100°C
Nitrogen -196°C
Sodium 883 °C
Common salt 1413°C
Silver 2162 °C
Carbon 4027 °C
Invisible steam
Water boils when it reaches its boiling point of 100ºC (212ºF). This is the temperature at which
water turns to steam. Steam is an invisible gas. When it reaches the lid it cools back to a liquid.
Evaporations
Even without boiling water in a kettle, some of the liquid water changes to gas. This is
evaporation. It occurs when a liquid turns into a gas far below its boiling point. There are always
some particles in a liquid that have enough energy to break free from the rest to become a gas.
Condensation
Dewdrops are often found on a spider’s web early in the morning after a cold night. Water that
is present as a gas in the air cools down and changes into tiny drops of liquid water on leaves
and windows. This change from gas to liquid is called condensation.
Exercises
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8. 1. Define, in your notes, each of the following:
a) Melt
b) Freeze
c) Evaporate
d) Condense
Part two: multiple choice questions
1. Ice cubes in a warm drink will
a. Melt
b. freeze
c. not change
2. The liquid drink _________ energy.
a. loses
b. gains
c. does not change
3. The ice ___________energy.
a. loses
b. gains
c. does not change
4. The final temperature of the ice and liquid is
a. the same
b. different
5. Which one of the following statement is not true?
a. the molecules in a solid vibrate about fixed position
b. the molecules in a liquid are arranged in a regular pattern
c. The molecules in a gas exert negligibly small forces on each other except during
collisions.
d. The densities of the most liquids are about 1000 times greater than those of gas
because liquid molecules are much closer together than gas molecules.
e. The molecules of a gas occupy all the space available.
Diffusion
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9. If someone is cooking in the kitchen it doesn't take long for the smell to travel around the
house to other rooms. This is because of diffusion.
Diffusion in gases
When chemicals, like the smell of perfume or burning toast, are let loose in a room, the
particles mix with the air particles. The particles of smelly gas are free to move quickly in all
directions. They eventually spread through the whole room. This is called diffusion.
You don't have to mix the gases by waving your arms around - it mixes on its own. Diffusion in
gases is quick because the particles in a gas move quickly. It happens even faster in hot gases
Diffusion in liquids
Diffusion can also happen in liquids. This is because the particles in liquids can move around
each other, which means that eventually they are evenly mixed.
For example if you drop a little bit of paint into a jar of water the colour will spread slowly
through the water. This is by diffusion.
Diffusion in liquids is slower than diffusion in gases because the particles in a liquid move more
slowly.
Solids
Diffusion does not happen at all in solids because the particles in a solid can only vibrate on the
spot, rather than being able to move from place to place.
Brownian motion
In 1827ropert brown discover that very tiny pollen grains suspended in water are continually
moving they make small, irregular movements in random directions, the particles in smoke can
be seen to do the same thing
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10. The effect is thought to be due uneven bombardment of the pollen or smoke particles by the
liquid or gas particles which surrounding them.
Very small particles are needed for the movement to be seen if the particles are large then
there will be equal numbers of collisions from every side and the effects will be cancel out but a
small particle is more likely to be unevenly bombarded, so it moves until struck again, the effect
can be seen in a smock cell it is called Brownian motion
 The kinetic theory explains Brownian motion as follows, the bits of smoke are just big
enough to be seen but have so little mass that they are jostled about thousands of particles
in the surrounding air bump in to them at random.
Properties of materials
Surface tension
• The interior molecules are equally attracted by all neighboring molecules with the
same force, so that the resulting force is zero.
• The molecules at the surface are attracted by molecules from inside, whereas no force
from outside the surface. Hence the resulting force is towards the interior of the liquid.
Surface tension: is defined as the force along a line of unit length, where the force is parallel to
the surface but perpendicular to the line
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11. Cohesion and Adhesion
Forces of attraction between a liquid and a solid surface are called adhesive forces. The
difference in strength between cohesive forces and adhesive forces determine the behavior of
a liquid in contact with a solid surface.
 Water does not wet waxed surfaces because the cohesive forces within the drops are
stronger than the adhesive forces between the drops and the wax.
 Water wets glass and spreads out on it because the adhesive forces between the liquid and
the glass are stronger than the cohesive forces within the water.
 When liquid water is confined in a tube, its surface (meniscus) has a concave
shape because water wets the surface and creeps up the side.
 Mercury does not wet glass - the cohesive forces within the drops are
stronger than the adhesive forces between the drops and glass. When liquid
mercury is confined in a tube, its surface (meniscus) has a convex shape
because the cohesive forces in liquid mercury tend to draw it into a drop.
Capillary action
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12. Capillary action (sometimes capillarity or capillary motion) is the ability of a liquid to flow in
narrow spaces without the assistance of, and in opposition to, external forces like gravity. The
effect can be seen in the drawing up of liquids between the hairs of a paint-brush, in a thin
tube, in porous materials such as paper
Summery
SURFACE TENSION: is defined as the force along a line of unit length, where the force is parallel
to the surface but perpendicular to the line.
INTERMOLECULAR INTERACTIONS
ADHESION force between two different bodies (or different surface layers of the same body) .
COHESION force attraction between like-molecules.
CAPILLARITY: is the ability of a liquid to flow in narrow spaces without the assistance of
external force.
 Before you choosing a material, a designer must know how it behaves under various type of
force.
Important properties are
 Strength : is the ability of material to resist beaking when stretched, compressed or
sheared
 Ductility: is the ability of a material to deform when a force is applied, plasticince is very
ductile, copper is ductile stainless steel is less ductile.
 Elasticity: is the ability of a material regains its original shape after being deformed,
spring steel is elastic so is rubber.
 Br ittleness: is the brittle materials break readily when their elastic limit is reached. They
do not show any noticeable extension when they are stretched they snap suddenly,
blackboard chalk, glass and dry twigs.
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13.  Sti ffness: is the resistance which the material offers to forces which tend to change its
shape or size, this can be effected by the shape of the article, a sheet of paper is stiff in
the plane of the paper but not stiff at right angles to it.
Questions
1. Define the following terms
a. Diffusion
b. Brownian motion
c. Surface tension
d. Cohesion
e. Capillarity
f. Stiffness
g. Ductility
2. Explain why?
a. Diffusion occurs more quickly in a gas than in a liquid
b. Diffusion is still quite slow even in a gas
c. An inflated balloon gradually goes down even when tied
3. Ahmed uses microscope to look at smoke particles he sees the smoke particles moving
randomly .what makes the smoke particles move randomly?
4. Why diffusion does not happen at all in solids?
5. Why diffusion in liquids is slower than diffusion in gases?
End
Prepared farah khatat
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