Matter is made up of tiny particles that are too small to be seen, even with a microscope. Experiments show that matter is composed of particles that can move and be transferred. Particles of matter have space between them, are continuously moving, and attract each other. The three common states of matter are solids, liquids, and gases, which have different characteristic properties depending on the strength of attraction between particles and how freely they can move. Changes in temperature or pressure can cause changes in a substance's state, such as melting, boiling, condensation, and sublimation.
EPANDING THE CONTENT OF AN OUTLINE using notes.pptx
class 9 chemistry Ch 1 matter
1. Anything which occupies space and has space is called
Matter. E.g., air, water, hydrogen, ice oxygen
MATTER
What is matter made up of?
Matter is made up of tiny pieces or particles.
The particle which made up matter are so tiny that we cannot see them
even with high powered microscope.
2. Experiment: To show that matter is made up of many tiny
particles.
Things required: - Beaker, potassium permanganate
(KMnO4), water.
Procedure: -
1.Take 2-3crystal of potassium permanganate and dissolve
them in 100ml of water.
2.Take out that approximately 10 ml of water and mix it in
another 90 ml of solution of clear water keep diluting
solution like this 5-8 times.
Observation: -
1. You will observe that 2-3 crystal will make 1st solution
colored.
2. And dilution shows that particles of matter are
transferred.
Conclusion: -This shows that matter is made up of many
tiny particles and shows that particles of matter are
transferred.
3. Chracterstics if Matter
Particles of matter have
spaces bettween them.
Particles of matter are
continiously moving.
Particles of matter
attract each other.
1. Particles of matter have spaces between
them:
Experiment:
Things required: - Beaker, Spatula, 100 ml water, 2 tea
spoon salt, Marker.
Procedure: -
1.Take 100 ml water in the beaker.
2.Mark the water level with marker.
3.Add 2 tea spoon of salt. stir it well.
Observation: - The water level remains same after
mixing 2 tea spoons of salt in 100 ml of water.
Conclusion: - The water level doesn’t increase because
when salt is dissolved in water, its crystal separates into
very fine particles. These particles of salt go into various
spaces between the various particles of water.
4. 2. Particles of matter are continuously
moving:
Experiment:
Things required: -Incense stick.
Procedure: -
1.Put an until incense stick in a corner of the room.
2.Now light the incense stick
Observation: - After some time the pleasant smell of
incense stick spread in whole room.
Conclusion: - when we light up incense stick in one
corner of the room the fragrance of incense stick spread
all over the room quickly because particles of incense
stick are continuously moving .
5. 3. Particles of matter attract each other:
Experiment:
Things required: -Ice, iron nail, chalk.
Procedure: -
1.Break ice, iron nail and chalk and note the observation
of force applied.
Observation: - you will observe that chalk need less force
to break, while ice need more force than ice to break and
iron nail don’t break.
Conclusion: - There is less force of attraction between the
chalk particles, so it breaks easily. While there is more
force of attraction in ice than chalk, so it requires more
force and the force of attraction in iron nail is very high so
it doesn’t break.
Force of attraction graph:-
Iron nail>ice>chalk
6. Properties Solid Liquid Gas
Shape Fixed
Not fixed
Not fixed
Volume Fixed Fixed Not fixed
Density High moderate Low
Type Rigid Fluid Fluid
Compressibility Negligible Negligible Highly
compressible
Spaces Minimum Moderate Maximum
States of Matter
solid
• E.g. wood iron
etc.
liquid
• E.g. water, HCl,
lactic acid
Gas
• E.g. oxygen,
hydrogen water
vapour
7. Diffusion: -
The intermixing of particles of different types of
matter is called diffusion.
This is a property of matter which is based on
motion (movement of its particles). Diffusion
occurs in solids, liquids and gases.
The rate of diffusion increases on increasing the
temperature.
solidification
fusion
We can change the state of matter in two ways
By changing temperature
By changing pressure
8. Changes in states of matter: -
The process of conversion of solid into liquid
on heating is called Fusion or melting.
The process of conversion of liquid into gas
on heating is called vaporization or
evaporation.
The process of conversion of solid to gas
without coming into liquid state on heating is
called sublimation. Sublimation occurs in the
following solids: -
1. Camphor
2. Iodine
3. Ammonium chloride
4. Naphthalene
5. Anthracene
The process of conversion of gas to solid
without coming into liquid state on cooling is
called deposition.
The process of conversion of liquid into solid
on cooling is called solidification or freezing.
The process of conversion of gas into liquid
on cooling is called condensation.
9. What happens on heating?
On heating of matter, motion of particles
of matter , kinetic energy and motion .
T
Solid Liquid
Change in state of
matter
What happens on cooling?
On cooling of matter, motion of particles of
matter ,kinetic energy and motion .
Liquid
T
Change in state
of matter
Solid
What happens on cooling and heating?
10. Melting point
The temperature at which solid melts in to
liquid at atmospheric pressure is known as
Melting point
Melting point of ice is 0°C.
Boling Point
The temperature at which liquid changes
into gas at atmospheric pressure is called
Boiling Point.
Boiling point of water is 100°C.
Latent heat
The heat required to convert a solid into a
liquid or vapour, or a liquid into a vapour,
without change of temperature.
There are three types of latent heat: -
1.Latent heat of fusion. (Solid to liquid)
2.Latent heat of vaporisation. (Liquid to gas)
3.Latent heat of sublimation. (Gas to solid)
11. 1.Latent heat of fusion
The amount of heat required by one kg of
solid to get converted into liquid
atmospheric pressure and at melting point is
called Latent heat of fusion.
2.Latent heat of vaporisation
The amount of heat required by one kg of
liquid to get converted into gas
atmospheric pressure and at melting point
is called Latent heat of vaporisation.
3.Latent heat of sublimation
The amount of heat required by one kg of
gas to get converted into solid atmospheric
pressure and at melting point is called
Latent heat of sublimation.
where is the heat going?
The heat is being absorbed by the particles of ice to overcome
force of attraction between them and get converted into water
12. Gases can be liquefied by applying pressure
and lowering temperature
When a high pressure is applied to a gas, it gets
compressed and when we also lower its temperature, it
also gets liquefied.so we can say that gases can be
liquefied by applying pressure and lowering the
temperature
Solid carbon dioxide is stored under high
pressure. Why?
This is because on decreasing pressure on solid carbon
dioxide gets converted directly into carbon dioxide gas
Ex- when slab of solid carbon dioxide gas is kept exposed
to air, then the pressure on its gets reduced to normal its,
temperature rises and gets converted into carbon dioxide
gas.
13. What is evaporation?
The process in which liquid changes into gaseous state at
any temperature below its boiling point is called
evaporation
Ex- drying of wet clothes, seasonal rivers, etc.
What is reason for evaporation
Particles of matter have different kinetic energy, some
particles of liquid have more kinetic energy than other
particles therefore they are able to overcome force of
attraction and convert into gaseous state.
Factors affecting evaporation
Surface area
Temperature
Humidity
Wind
How dose evaporation causes cooling?
For e.g., we have water particles that have to convert
into water vapor and it needs energy to break their
force of attraction to change its state from liquid to
gas.
They will take energy from their surrounding (the
energy used to change state is latent heat of
vapourisation).
And after evaporation the heat energy from
surrounding will be used in evaporation so
surrounding becomes cool.
Hence proved evaporation causes cooling.
14. The Unit Of Temperature
The SI unit of temperature is kelvin.
0°C= 273.15 kelvin (but for calculation we use
273K).
0°C = 32°Fahrenheit
Conversion of unit:
-
Celsius to Kelvin
Temperature in K= temp in °C+273
Kelvin to Celsius
Temperature in °C= temp in K- 273
Celsius to Fahrenheit
℉ = (
9
5
× ℃) + 32
or
℉ = 1.8 × ℃ + 32
Fahrenheit to Celsius
℃ =
5
9
(℉ − 32)
15. Experiment: To show that water vapour
is present in air
Things required: - tumbler, crushed ice
Procedure: -
1.Put the crushed pieces of ice in the tumbler.
2.And absorb some time
Observation:- after some time you will absorb water
droplet on the outer surface of the tumbler.
Conclusion:- water vapour present in air, on coming
with contact with cold glass of water, losses energy
and get converted into liquid state which we see as
water droplets.
Is there water vapour present in air ?
16. Question and answer
Q. Happens What when you put some acetone (nail polish remover) on your
palm?
Ans. Acetone, petroleum and perfume are violated substance that
evaporate when that come in contact with air, evaporation in facilitated as
it uses energy from your palm, leaving the cooling effect on your palm.
Q. After a hot sunny day people sprinkle water on the roof or open ground.
Ans. When water is sprinkled on the roof or the open ground it
evaporates because of latent heat of vapourisation leaving behind the
cooling effect.
Q. Why are we able to sip milk or tea faster from the saucer rather than cup?
Ans. A saucer has a large surface area than cup, promoting evaporation.
Hence, the tea or milk cools down faster.
Q. why should wear cotton cloths in summer?
Ans. In summer it is preferred to wear cotton cloths in summer because
cotton clothes have pores in them to absorb sweat, facilitating
evaporation, and causing cooling effect on the skin
Q. How does a desert cooler cool better on a hot dry day?
Ans. It is because temperature is less on a hot dry day, enabling better
evaporation. High level of evaporation provides better cooling effect.
Q. How does the water in earthen pot becomes cool during summer?
Ans. The water kept in an earthen pot seep into the small pores in the pot
and evaporates from the surface of the pot. The heat required for
evaporation is taken from water inside the pot, thus cooling the water
stored inside. This is the reason why on hot summer days water remains
cool in earthen pot.
17. EVEAPORATION BOILING
1.Takes place at all
temperature.
1. It takes place only at
boiling point.
2.It causes cooling. 2. It does not causes cooling.
3.It is a surface phenomenon
i.e., starts from the surface.
3. It is a bulk phenomenon i.e.,
Starts from bulk.
Q. Difference between evaporation and boiling?