There are three main states of matter: solids, liquids, and gases. Solids have a fixed shape and volume, liquids have a fixed volume but take the shape of their container, and gases fill their container evenly. Matter can change between these three states through processes like melting, freezing, evaporation, and condensation. When a solute dissolves in a solvent, it forms a solution, and soluble and insoluble substances can be separated from solutions through methods like filtration, sedimentation, and decantation.

1. Solid, Liquids and Gases
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2. States of matter
 Any substance that has mass and occupies space is
called matter.
 Matter is made up of small particles.
 Three states of matter
 Solid
 Liquid
 Gas
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3. States of matter
Solid Liquids Gases
Particles are packed very
close to each other.
Particles are not very
closely packed
Particles are very loose
packed.
Usually hard and have a
fixed
shape
• Have no fixed shape
and can flow.
• They take the shape of
the container they are
poured into.
• Have no fixed shape.
• They occupy all the
available space in a
container.
On Applying Force
• Some solids can change
their shape
• Some solids can be bent
or broken
Liquids are also called
fluids as it can flow from
one place to another.
Gases are also fluids
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4. States of matter
Pencil, book, chair, and
marbles are some examples
of solids.
Water, milk, and juices
are some examples of
liquids.
Air and cooking gas are
some examples of gases.
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5. Changes of State
Condensation
Gas
Heat Cooling
Solid
Liquid
FreezingMelting
Evaporation
• Matter can change from one state
to another.
• The process by which a solid
changes to liquid is called
melting.
• The process by which a liquid
changes into a vapour is called
evaporation.
• The process by which a gas
changes into a liquid on cooling
is called condensation.
• The process by which liquid
changes into a solid is called
freezing.
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6. Solute, Solvent and solution
 The solid that dissolves in a liquid is called the
solute.
 The liquid in which the solute dissolves is called the
solvent.
 The liquid that we get when a solute dissolves in a
solvent is called a solution.
Solute + Solvent = Solution
Solute Solvent Solution
Sugar Milk Sweet Milk
Salt Water Salty Water
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7. Separation of Substances
 Soluble substances are those substances that dissolve
completely in water to form a solution. E.g. Salt ,Sugar
 Soluble substances can be separated by heating.
Salt solution Water evaporates and salt
particles are left behind.
Heated
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8. Separation of Substances
 Insoluble substances are those substances that do
not dissolve completely in water. For example sand
and chalk.
 Insoluble substances can be separated a solution by
the processes of
1. Filtration
2. Sedimentation
3. Decantation.
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9. Separation of Substances
 Filtration : Solution is
passed through a filter
paper. Liquid passes through
the filter paper, while the
soluble substance gets
retained on the filter paper.
 For example, sand and
Water can be separated by
filtration.
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10.  Decantation is a fast method for separating a
mixture of a heavier solid and a liquid.
 For separating the mixture of water & sand, first, we
should let the sand to settle on the bottom of the
container (sedimentation). Then we pour off the
water at the top into the other container.
Separation of Substances
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