zainab bt. ariffin (90286)
DESCRIPTION
CHANGES IN THE STATE OF MATTER. Presented by:. Zainab Bt. Ariffin (90286). MATTER. Matter is anything that occupies space and has mass. Matter is made up of tiny and discrete particles. These particles are: Atom. Molecule. Ion. Matter exist in 3 states :-. Liquid. - PowerPoint PPT PresentationTRANSCRIPT
MATTER
Matter is anything that occupies space and has mass.
Matter is made up of tiny and discrete particles.
These particles are: Atom. Molecule. Ion.
Matter exist in 3 states :-
Solid
Liquid
Gas
Solid .
A solid has afixed volumeand shape.
A solid cannot be compressed
The particles are packed closely together in an orderly manner.
There are strong forces between the particles.
The particles can only vibrate and rotate about their fixed positions.
Liquid
A liquid cannot be compresseasily.
A liquid has a fixed volume. It does not have a fixed shape but takes the shape of the container.
The particles are held together by strong forces butweaker than theforces in a solid.
The particles can vibrate,rotate and move throughout the liquid. They collide against each other
The particles areclosely togetherbut not in orderly arrangement
Gas
A gas does not have a fixed shape or volume.
A gas canbe compressed
easily.
The particles are veryfar apart from each other and in a randommotion.
There are weak forces between the particles.
The particles can vibrate, rotate and move freely. The rate of collision is greater than the rate of collision in a liquid.
Inter-conversion of the state of matter
GAS
SOLID LIQUIDKey : :heating
:cooling
Subl
imat
ion evaporation
condensation
freezing
melting
Subli
mat
ion
decreasing heat
increasing heat
solid liquid
The change in heat affects the kinetic energy of particles
gas
Melting pointWhen solid is heated , the particles in thesolid gain kinetic energy and vibrate morevigorously.
The particles vibrate faster as thetemperature increases until the energy theygained is able to overcome the forces thathold them at their fixed position.
At this point, the solid become liquid
This process called melting
The temperature at which this happen iscalled the melting point.
Freezing Point When a liquid is cooled, the particles in the
liquid lose energy and move slower.
As the temperature continues to drop, the particles continue to lose more energy until they do not have enough energy to move freely.
At this point, the liquid changes into the solid
This process is called freezing
The temperature at which this happen is called freezing point
Meltingpoint
Temperature (°c)
Time (min)
The heating curve
A
B C
D
At point A :-The matter exists as solid. When the solid
is heated, heat energy is absorbed.This cause the particles to gain kinetic
energy and vibrate faster.This is why the temperature increases.
At point B to C :-The solid begin to meltBoth liquid and solid are presentDuring the melting process , the
temperature of the matter does not rise, even though heating continues.
The temperature remain constant because the heat energy absorb by the particles is used to overcome the forces between particles so that the solid can turn into liquid.
This constant temperature is the melting point of the matter.
At point C and D :-
All the solid has melted and change to the liquid
From point C to Point D, the particles in liquid matter absorb heat energy and move faster.
The temperature increases from point C to D.
The cooling curveTemperature
(°c)
F G
H
E
Time (min)
Freezing point
At point E to F :
The particles in the liquid lose their kinetic energy
They move slower as the temperature decrease
At point F :-
The liquid matter begins to freeze.
Its temperature remains constant because the heat loss to the surroundings is exactly balanced by the heat energy liberated as the particles attract one another to form solid
At point G to H:-
The solid is cooled
The particles in the solid vibrate slower as the temperature decreases