1. Made by: Anya Rakhecha
IX-D
Roll no.:39

4. The particles of matter are very small ,they are
small beyond our imagination! These particles are
called atoms. All objects we see from naked eyes are
made of atoms. This atomic matter is in turn made up of
interacting subatomic particles—usually a
nucleus of protons and neutrons, and a cloud of
orbiting electrons.

5. In Solids, The particles are packed
closely together. The forces between
particles are strong enough so that the
particles cannot move freely but can
only vibrate. As a result, a solid has a
stable, definite shape, and a definite
volume.
A liquid is a nearly
incompressible fluid that conforms to
the shape of its container but has a
fixed volume. Intermolecular force is
less that solid in liquids but
Intermolecular space is more in liquids
than in solids.
A gas is a compressible fluid. Not only will a
gas conform to the shape of its container
but it will also expand to fill the
container.In a gas, the molecules have
enough kinetic energy so that the effect of
intermolecular forces is small, and

6. The forces of attraction between the particles are
maximum in solids, intermediate in liquids and
minimum in gases. This Force is called
Intermolecular Force. Intermolecular force is the
increases with decrease temperature.

7. The arrangement of particles is most ordered in the case of
solids, in the case of liquids layers of particles can slip and
slide over each other while for gases, there is no order, particles
just move about randomly.

9. Evaporation is a surface
phenomenon. Particles from the
surface gain enough energy to
overcome the forces of
attraction present in the liquid
and change into the vapour
state
The rate of evaporation
depends upon the surface area
exposed to the atmosphere, the
temperature, the humidity and the
wind speed.
 Evaporation causes cooling.

10. Latent heat of
vaporisation is the heat
energy required to change
1 kg of a liquid to gas at
atmospheric pressure at
its boiling point.
 Latent heat of fusion is
the amount of heat energy
required to change 1 kg of