The properties of fluids and the Particle

Model
Solid – Has a definite shape and volume.

Liquid – Has a definite volume, but no definite

shape.

Gas – Has neither a definite shape or volume.

Particles in Solids
– Particles are so tightly packed together that they
can’t move around freely...they can only vibrate.

- Solids are greatly affected by gravity and will move

to the lowest point.

- Solids can be ground into small pieces so that they

can be poured...but each piece is still a solid and
they pile up on each other and can’t flow.

- Examples of solids that can be poured are :

detergents, drink crystals, salt, sugar.
Particles in Liquids
- Particles have enough energy to pull away from
each other...therefore they can slide (flow)
around each other while still vibrating close to
each other in small groups.

- Liquid particles are packed tightly enough

together that they are affected by gravity.
Liquids will always flow to the lowest point.
Particles in Gases
- All liquids can be transformed into their gaseous
state when liquids are heated.

- Gas particles are so far apart that there is an

enormous amount of empty space between them.

- Most gases seem invisible because there is so much

space between particles.

- Most gases do not flow to the lowest point as do

liquids and solids. Because gas particles are spread
out so much, they move in all directions, sometimes
against gravity and remain suspended.
The Particle Model of Matter

1. All substances are made of tiny particles.

2. All particles in a pure substance are the same.

Different pure substances are made of different
particles.
3. The particles have spaces between them.

4. The particles are always in motion – vibrating,

rotating and (in liquids and gases) moving from place
to place. The speed of the particles increases when
temperature increases and speed decreases when
temperature decreases.

5. The particles in a substance are attracted to one

another. The strength of the attractive force
depends on the type of particle.
Take a break
 Classification of Matter
All Matter
Mixtures
Pure Substances •Containtwo or more pure
substances.
•Contain only one type of particle.

•Canexist in three states of

matter – solid, liquid and gas. Heterogeneous
Homogeneous
(solutions) (mechanical)
mixtures
• Appear to be one
•Two or more parts
substance.
• Different kinds of can be seen.
• Different kinds of
Elements Compounds particles intermingle.
• Examples : particles stay
•Examples : iron, •Examples : water, vinegar and clean air together.
• Examples : soil,
gold and oxygen. salt and sugar.
blood and concrete.
Pure Substances

Elements
- Pure substances can be seen in the Periodic Table of
Elements. These are the only pure substances that we
know of and each individual substance in the table is an
element.

Compounds
- The elements in the Periodic Table of Elements are
combined to make compounds of pure substances.
Compound means made of two or more elements.

- Compounds have very strong chemical bonds and as the elements combine, they lose
their individual characteristics.

- Forming a compound requires a chemical reaction. Compounds cannot be separated by

physical means such as evaporation.

NaCl – Table Salt

NaHCO3 – Baking Soda
NaOH – Drain Cleaner
NaOCL – Bleach
Minerals - Quartz
Mixtures

Homogeneous (Solutions)
- Look like they are made of one substance.

- When there is no settling of substances, it is called a solution. Solutions

happen because each particle slips between each other particle so they are
evenly distributed.

- A solution or Homogeneous mixture has equal parts of both substances.

- There are no chemical bonds in Homogeneous solutions. Also when the

substances combine they still keep their individual characteristics. When sugar
combines with water, the sugar still tastes sweet.

- Forming a mixture does not require a chemical reaction, you simply have to
combine substances.

- Mixtures can be separated by physical means like boiling.

Can you name some homogeneous solutions that you may find in your home?

Salt Water
Corn Oil
White Vinegar
Pure Water
Heterogeneous (Mechanical mixtures)
- The substances in a heterogeneous mixture are not hidden.

- If there are two or more substances visible within a mixture, then it is called
heterogeneous.

- Heterogeneous mixtures can be separated by mechanical means such as using a

filter or using your hands.
Can you name some heterogeneous mixtures that you may find in your home?
Italian salad dressing
Chunky spaghetti sauce

In Between Mixtures
- A heterogeneous mixture that looks homogeneous, but has particles slowly settle
over time is called a suspension.

- A heterogeneous mixture in which the particles do not settle is called a colloid.

Can you name some In between mixtures that you may find in your home?

Orange Juice
Milk
Homogeneous and Heterogeneous Video

Take a break
Why do materials dissolve?
- Forming a solution by mixing two or more materials
is called dissolving.

- Dissolving happens because particles attract each

other and are always moving.
How do we know this?

Example – When we mix sugar and water, the water

particles have a stronger pull on the sugar particles
than the other sugar particles do. Also, because the
particles are always moving, they can move beside
each other and the attraction happens more. The
particles of sugar eventually move around and mix
evenly with the water.
Solutes and Solvents

Example – Sugar being dissolved in water.

- The solute is the substance (sugar) that dissolves in the

solvent (water) to form a solution.

- The solvent (water) dissolves the solute (sugar) to form

solution.

- There is usually more solvent than the solute in a solution.

- Sugar can dissolve in water, therefore sugar is soluble in

water. Soluble means able to be dissolved in a particular
solvent. Something that is insoluble is unable to dissolve in a
solvent.
Try and think of two more examples of something being dissolved
and tell me what is the solvent and what is the solute.
The Universal Solvent

Water is called the universal solvent because it

can dissolve so many substances.
The Rate of Dissolving

Rate of dissolving is how fast a solute dissolves in

a solvent.

Factors that affect the rate of dissolving

- Agitation helps the solutes dissolve faster.
- Smaller pieces dissolve faster than larger
pieces of a substance.
- In many substances the rate of dissolving
increases as temperature increases.
How much can be dissolved?

Solubility is the mass of a solute that can dissolve

in a given amount of solvent to form a saturated
solution at a given temperature.

A saturated solution is when no more solute will

dissolve in a solvent.

An unsaturated solution is when more of a solute

can still dissolve in a solvent.

A supersaturated solution is when a solvent

contains more solute than can normally be
dissolved.
Using the Particle Model of Matter to explain
mixtures and solutions

- The Particle Model of Matter says : The particles in a

substance are attracted to one another. The strength of
the attractive force depends on the type of particle.

- So particles that make a solution would have stronger

attractions to each other, where as particles in mixtures
would not have as strong of attractions to each other.

- The Particle Model of Matter also says : That

particles are always moving. Therefore it is easier
for them to mix together and the attraction
between particles can work quicker.
Take a break
 WHMIS SAFETY SYMBOLS
Workplace Hazardous Materials Information
System
 States of Matter
and the Particle
Model of Matter

3 States of Particle Model of

Matter Matter
What are the 5 parts of The
Particle Model of Matter

___ ___
What are 3 What are 3 characteristics
characteristics of a of a ____?
____?
____
What are 3 characteristics of
a _____?
 Classification of
Matter

Mixtures
Pure Substances
Homogeneous
(solutions)

Give 3 characteristics of
Elements Homogeneous Solutions and give
3 examples.
Where can we find ______
elements and name _______
two? What are two characteristics (mechanical)
mixtures
of ____ and give two
examples?
Give 3 characteristics of
_____ Solutions and give 3
examples.
With a partner, try to explain some ways that
we can separate different mixtures that are
found in the Earth. If you need to look in the
textbook then do so.

Write your answers point form in your Science

Journal
Desalinating Water
- Salt water is heated and water evaporates
- Salt is left behind while water vapour condenses on plastic
sheet and is collected in containers
- Condensed water is now free of salt and ready to drink

Processing Petroleum
- Petroleum is heated and turned into a gas
- The gas then passes into a tower
- At each level of the tower, different petroleum products
(gasoline, jet fuel, kerosene, tar) condense and separate out
- The different products condense at different
temperatures...those that condense at cooler temperatures
condense towards the top of the tower
Extracting Gold
- Gold ore (rock with gold in it) is crushed and mixed
with water to create a suspension
- Chemicals are added to make the gold dissolve and
only the gold will dissolve
- The dissolved gold can then pass through a filter,
while all other material is caught in the filter
- The gold is then released from solution and settles
to the bottom and is collected

Collecting Sea Salt

- Sea salt is collected in large open pools
- The water evaporates and leaves the salt behind in
the pools
With a partner, try to explain what flow rate
and viscosity mean. Also try to name some
substances with different flow rates and
viscosities...and explain the difference
(whether the substance has a high viscosity
or low viscosity, slow flow rate or fast flow
rate). You may need to look in your textbook.

Write your answers point form in your Science

Journal
- A liquid’s thickness or thinness is called
viscosity. A thicker fluid would be more viscous

- The time it takes a fluid to flow from one point

to another is called a fluid’s flow rate
Products and the importance of flow rate

Motor Oil
- Motor oil must be viscous enough to cover
engine parts and lubricate them
- However, motor oil must also be thin enough to
reach engine parts as soon as vehicle is started

Would you use a thicker engine oil in the winter?

Explain and think about the Particle Model of
Matter.
Take a break
Oil extraction from oil sands
- One method is to use steam and inject it
underground
- The steam heats the oil sands and makes the oil
thinner or less viscous
- The oil can then be pumped out of the ground

Nail Polish
- Viscosity is important
- If too thin it will flow too fast and dry slow and if
too thick it will flow slowly and dry too fast

Can you think of at least two other products where

viscosity is important?
How does the viscosity of liquids vary?

- As temperature of a liquid increases, the

viscosity decreases meaning it can move quicker

- As temperature of a liquid decreases (gets

colder), the viscosity increases meaning it will
move slower
How does the viscosity of gases vary?

- As the temperature of a gas increases, the

viscosity increases as there are more collisions
between the gas particles. The increased
collisions mean it is harder for the gas to move.

- As the temperature of a gas decreases (gets

colder), the viscosity decreases meaning it will
move quicker

- The above relationship is the opposite of liquids.

With a partner, try to explain what density is
and write down some examples of things that
have a high density and some with a low
density. If you need to look in the textbook
then do so.

Write your answers point form in your Science

Journal
Density is the amount of mass in a certain unit
volume of a substance. In a substance that is
more dense, the particles are more “crowded”
together.

Knowing the above fact, list the states of matter

from most dense to least dense.
Take a break
Solids – The particles in a solid are tightly packed together, therefore solids
are the most dense state of matter.

Liquids – The particles of a liquid are more spread out than solids but less
than gas. Therefore, liquids are less dense than solids but more dense
than gas.

Gas – Gas particles are the most loosely packed together so gases are the
least dense state of matter.

o In most pure substances, the solid state of a substance is more dense

than it’s liquid state. The solid and liquid states are then in turn more
dense than the substances gas state. Water is the exception.

Can you explain this?

Ice floats on water, therefore it must be less dense than water.

o However, one substances solid state may be less dense than another
substances liquid state. Also, the liquid state of one substance can be
more dense than the liquid state of a different substance as can a solid
compared to another solid. Can you think of examples?
Think about the Particle Model of Matter and
use it to answer the following question:
When a state of matter is heated, does it
get more or less dense?

When a state of matter is heated, the particles speed

up and spread out more. If they spread out more,
then there is more space between particles. This
then means that as a state of matter is heated, it’s
density decreases.

Remember...if there is more space between particles in

a substance, then the density is lower.
Measuring Density

Density takes into account mass and volume.

Mass – The amount of matter in a substance

Volume – The amount of space occupied by a substance

Density = Mass / Volume (D = M / V)

Density of a substance stays the same as long as the

temperature and pressure stay the same
Can you explain how pressure would affect Density?
Take a break
Try to explain what buoyancy is. Also take a
look at Archimedes Principle and try to
explain how this works. If you need to look in
the textbook then do so.

Please write your answers in your science

journal.
Buoyancy
Buoyancy is the tendency for materials to sink or rise in a fluid.

Buoyancy is also known as the buoyant force…it is the upward

force exerted on objects submerged in fluids (gas or liquid).

What are some important things that rely on buoyancy to work?

• Moving nutrients in our bloodstream
• Pollen floating through air
• Planes and boats transporting goods
The Anti-Gravity Force
The particles of a fluid exert a force in a direction opposite gravity.
Gravity pulls down, whereas buoyancy pushes up.

How can things like Supertankers (very big ships) float on water when
their density is more than water?

Average Density
If the average density (the total mass of the substance and everything
on it divided by the total volume) is less than the density of the
water then it will float.

How do they reduce the average density of large ships? How do we

reduce our average density when in a boat to help us float?
Archimedes Principle Video

Censored

Archimedes Principle Video 2

Censored
Benefits of average density

What are some benefits of average density? Give two

examples to show how average density would work.

Average density is useful because it helps objects that

would otherwise sink, to float. It can also help
floating objects to sink.

o Swim bladder in a fish helps it rise and sink in the

water
o Life jackets on a person help us float..it lowers our
average density
o The amount of that in a submarine determines if it
rises or sinks
o The large volume of a blimp compared to its weight
Archimedes Principle

The buoyant force acting on a an object equals the

weight of the fluid displaced by the object.

How are buoyancy and density related

The buoyant force of a liquid and a gas depends on

density. A liquid or gas that is more dense, can
support more weight per volume than a liquid or gas
that is less dense.

Example : Salt water is more dense than fresh water.

Salt water can support more weight per volume than
fresh water…so you would float better in salt water
than fresh.
 Separating Earth’s Flow Rate and
Mixtures Viscosity

Flow Rate
? ? What is Flow Rate?
Give two examples of how we can
separate mixtures found in
Earth. Describe each process.
Viscosity
What is Viscosity?

Products that depend How viscosity changes

on Viscosity in liquids and gases

? ? Liquid Gas
Name two products that Describe how viscosity changes
depend on viscosity and in liquids and gases
describe how viscosity is
important to the product
 Buoyancy
Density
What is Buoyancy?
What is Density?

The Anti-Gravity Force

Explain how Buoyancy is the

Density of the Change of density when Anti-Gravity force
Three States of heated
Matter
Use the Particle Model of Matter to Average Density
explain how density changes when a
state of matter is heated Explain what average
Liquid Gas density is and why it is
useful
Relationship between
Solid Archimedes Principle
buoyancy and density
Explain the density of the Explain what Archimedes
three states of matter Principle is and give an What is the relationship
example between buoyancy and density?

Examples of
Average Density

Give two examples of

average density working
Take a break
Compression of a gas
Why a gas can compress:
• The gas must be enclosed in a sealed container with strong walls so
the molecules can distribute themselves through the container.
• There is so much space between gas particles, so even after they
are compressed, space between the particles still exists so they still
act like a gas.
• An external force is applied to the gas to push the particles
together.

Why other states of matter can’t be compressed

• The particles are almost as close as possible so when a force is
applied to them, they can’t move much closer together.
• Gas can be compressed because there is lots of space between
particles.
Advantages of Compression
Gas can exert a counter force back when compressed. This is useful
for:
• Car tires – The tires push back against the weight of a car
otherwise they would just collapse.
• Air bags – They absorb the shock of a crash to protect
passengers.
• Shock absorbers in a vehicle – They absorb the force from
hitting bumps in the road.

Atmospheric Pressure
• Air pressure changes with altitude. As you go higher in the
atmosphere the pressure gets lower. This happens because
there are less particles above you pushing down.
• When going up in an airplane your ears pop because your body is
trying to equalize the pressure inside your body with the
pressure outside your body.
Does pressure increase or decrease when you go under water and
why?
Balanced and Unbalanced Forces
• If the inside of a container experiences lower pressure than
the outside, the container will collapse.

Example – Drinking juice in a drinking box.

• If the inside pressure of a container is higher than the

outside, the container will expand.

Example – Carrying a container of pop on an airplane. Once in the

air the bottle expands slightly and you need to release the
pressure.
Take a break
Hydraulic Systems
• Hydraulics are the study of pressure in liquids.
• Devices that transmit forces through a liquid to move
something, due to pressure, are called hydraulic systems.

Hydraulics to transport fluids

• Liquids under pressure flow away from the pressure source.
• Hydraulics can be used to transport fluids over long distances.
• Pumps provide the pressure source to move the fluids.
• Moving gas, water and oil are done with pipes and hydraulics.
Pressure and Pneumatic Systems
• Pneumatics are the study of pressure in gas.
• The operation of pneumatics is based on the fact that gas can
be compressed.
• As gas is decompressed, the particles start to move apart
suddenly, creating a steady force to perform tasks.

Devices that use Pneumatics

• Dentist drills, air brakes in big trucks, dirt tampers.