MATTER………
CONCEPT MAP:
Matter
Material
Object
Substance
Mixture
(impure
substance)
Pure substance
Metal
Element
compound
Homogeneous
Heterogeneous
Metalloid
Non-metal
solution
suspension
STATES OF MATTER:
• States of matter: Physical forms of matter are called state of
matter.
• The Phusical Status of Matter: There are mainly three different
kinds of physical kinds of states of matter, namely
- Sold
- Liquid
- Gas
Plasma : a fourth class of matter has also been identified.
These states of matter are also termed as phases.
Substances can exists in different matter under different temperature and
physical conditions.
changes in temperature and pressure can change the states of matter.
SOLID:
Solid: Solids are identified by their definite shapes and their considerably
mechanical strength and rigidity. Solids tents to resists the deformation of their
shape due to strong molecular forces. A solid is relatively non compressible,
i.e. normal temperature and have only slightly effect on their volume.
Solids are broadly classified as:
Crystalline solid (regular solid) : Here atoms are arranged in a definite pattern
Which is constantly repeated.
Amorphous solid(irregular solid): These have no geometrical form.
The molecular mode of solid:
- Molecules are closely packed.
- Strong molecular attraction .
- Molecules with restricted movement.
- Intermolecular space is minimal.
- Not compressible.
- Have enough kinetic energy to only vibrate
and rotate about their fixed position.
Hence, a solid has a fixed shape.
LIQUID:
Liquid: A liquid has no definite shape and it takes the shape of the vessel containing it.
A liquid has volume which is slightly altered by variation of temperature and pressure.
Liquids have three typical physical properties:
Vapour pressure: A liquid when kept in a closed container vapourised into free space
above it. The process of vaporization will continue till the equilibrium is reached
Between liquid and vapour. The vapour and the liquid can co-exists is called the vapour
Pressure of the liquid at a given temperature.
Surface tension: The surface of a liquid is always in a state of tension because a molecule
of the surface is attracted towards the bulk by a force much greater than that drawing it .
Viscosity: It determines the flow of liquid. It is the internal friction between the layers of
liquid. Greater the viscosity of the liquid, its flow will be retarded and vice versa.
The molecular mode of liquid:
- Molecules are not closely held.
- Less intermolecular attraction.
- More intermolecular space.
- Compressible.
- Have more kinetic energy. Particles are not
held in fixed position. This is why a liquid
has no fixed shape.
GAS:
Gas: A gas has no bounding surface at all and occupy completely any vessel in which it is
filled. It has no definite volume and shape and can easily be expanded or compressed.
The molecular mode of gas:
- Molecules are far apart.
- Weak intermolecular attraction.
- More intermolecular space.
- Easily compressible.
- Have more kinetic energy. Particles are not held in fixed position.
Thus a gas has no fixed shape.
PROPERTIES OF SOLID, LIQUID AND GAS COMPARISON
PROPERTY
SOLID
LIQUID
GAS
Shape
Definite shape
No definite shape,
take the shape of
the container.
No definite shape,
take the shape of
the container.
Volume
Fixed volume
Fixed volume
Any volume.
Density
Normally high
density.
Moderate density.
Very low density.
Compressibility
Not compressible.
Not easily
compressible.
Easily compressible.
(e.g. CNG)
Ease of flow
Do not flow.
Flow.
Easily flow.
Mass
Larger mass of
constant volume.
Lower mass of
constant volume.
Lightest mass of
constant volume.
Hardness
Normally hard.
Not hard.
Not at all hard.
Random.
Very random.
Arrangement of In a regular
particles
pattern.
CHANGING
WORDS
STATES
OF
MATTER:
KEY
 Melting : If a solid is heated, it expands and then melts. When a sold is
changed into liquid, it is melting. Example: Ice to water.
 Freezing(solidification): If a liquid is cooled sufficiently, the liquid will turn
into solid. When a liquid is cooled into a solid, it has undergone freezing
(solidification). Example : Water to ice.
 Evaporation: Liquid cab be changed into gas without boiling (no additional
heat is given), it is evaporation. It is much slower process than boiling. For
example, if a glass of water is left open under normal atmospheric temperature,
water slowly changes into water vapour(gas). This happens due to evaporation.
 Boiling: Liquid can also be changed into gas when additional heat is applied.
This is boiling. It is a faster process. Example, water turns into steam at 100 C
(normal room temperature is 25 C).
KEY WORDS:
 Condensation: If a gas is sufficiently cooled, it changes into liquid. This is
called condensation. Example, breathing onto a cold window causes water
vapour in your breath to condensed.
 Sublimation: Few solid substances , when heated, changed into gases without
being change into liquid first- they sublime. This process is called sublimation.
Example, dry ice ( solid carbon dioxide) turns into gas without being cha need
into liquid.
 Deposition (or solidification) : It is the opposite of sublimation. Some gases
can be changed directly into solid without being changed into liquid when
temperature is reduced to higher freezing points. This process is called
deposition or sublimation. Example, sulphur gas deposited into solid sulphur
as it cools after leaving volcano.
Water is a unique example of matter that exists in three different states.
DIFFERENCES BETWEEN BOILING AND EVAPORTION:
Boiling
Evaporation
Extra energy is needed.
Normal room temperature is enough.
This is a faster process.
This is a slower process.
Bubbles form during boiling.
No bubble forms.
Occurs from inside the liquid.
Occurs on the surface of the liquid.
HOME WORK QUESTIONS:
1. What is matter made up of ?
2. Why are gases easier to compress ? Justify your with example.
3. Normally solid can’t be compressed or stretched. Name two solids that can be
compressed or stretched.
4. Make a table with three columns (solid, liquid and gas) and classify following
materials accordingly:
Rock, sea water, flour, vinegar, steam, smoke, custard, butter, diamond, oxygen, ice,
diesel, air, spirit, dry ice, table salt, a grain of sugar, orange juice, dew, cloud, brick.
5. Water is a classic example of matter that can exist three different state. Name and
explain two other materials which can also exist in different state.
6. What are the names of solid state of water and carbon dioxide gas?
7. What is the state of matter called compressed natural gas (CNG)?
8. In the following , which is the odd state?
Alcohol, oil, mercury, oxygen.
9. What are the differences between evaporation and boiling?