This chapter is about Matters And Our Sourroundings

1.  Prepared by-
 Name - Yashovardhan Phadtare
 Class - 9
 Academey – Wilson’s Coaching Academy
Pune

2. They classfied the elements into 5 states .
Ancient Greeks also classified elements into 5
states of matter.
These 5 elements were –
 Air
 Earth
 Fire
 Sky
 Water

3.  Anything which has mass and occupies space
called as Matter.
 E g- water , crystals of copper sulphate etc.

4. Take 2-3 crystals of potassium permanganate
(KMnO4) and dissolve them in 100 ml of water.
Take out approximately 10ml of this solution
and put it into 90 ml of water.
Take 10 ml of this solution and put it into
another 90 ml of clear water.
Keep diluting the solution up to 5-8 times.
Is the water still coloured?
This shows that just a few crystals of KMnO4
can colour a huge amount of water. So we
can conclude that there must be millions of
tiny particles in just one crystal.
You can do same with dettol.
You can also watch this activity by give link-
https://youtu.be/ikOA8i055yQ

5.  Solid
 Liquid
 Gas
 Plasma
 Bose – Einstein Condensate

6. It is state of matter in which atoms are tightly
bonded to each other.
Properties of solid state of matter –
i)All of these have a definite shape.
ii)They have distinct boundries and fixed
volume.
iii) Tightly bonded solid are very rigid.
Atoms in solid state of matter-

7.  A liquid is a nearly incompressible matter.
 Properties of liquid -
i) In water atom bonding is partially loose.
ii) It has not definite shape but they have fixed
volumes.
iii) Liquids flow and change shape , so they are
not rigid but they can called as fluids.
Molecules in liquid state of matter-

8.  In gas atoms are very loosely bonded with
each other.
 Properties of gas-
i) They have high compressibility.
ii) Most gases are difficult to observe directly.
iii) They have the fast diffussion property.
iv) The particles move randomly at high speed.
Atoms in liquid state of matter-

9.  Take three 100 ml syringes and close their nozzles by rubber
corks.
 Remove the pistons from all the syringes.
 Leaving one syringe untouched , fill water in the second
syringe and pieces of chalk in third.
 Insert the pistons back into syringes .You may apply some
vaseline to the piston before inserting them into the syringes
for their smooth movement.
 Now ,try to compress the content by pushing piston of each
syringe.
 The piston of syringe containing air moves easily, while piston
of syringe containing water needs some pressure & piston of
syringe containing chalk is most hard to move.
 We observed that gases are highly compressible compared to
liquid and solid.

10. Tight bonding Loose bonding Least bonding

11. Yes, matter can change its state.
We all know the states of water.
 When water is in solid state it is called as
ice.
 When water is in liquid state it is called as
water .
 When water is in gaseous state it is called as
water vapour.

12. It is a process of changing of state of matter
in which matter converts from solid phase to
vapour phase without changing into liquid
phase and vice- versa.
Eg – Camphor , Naphthalene ball , Iodine ,
ammonium chloride etc.

13.  Evaporation is the process by which water
changes from a liquid to a gas or vapour.

14.  Surface area: Increase in surface area of
water will increase its rate of evaporation .
 Temperature: Increase in temperature of
water will increase its rate of evaporation .
 Humidity: Increase in humidity of air will
decrease its rate of evaporation.
 Wind Speed : Increase in wind speed will
increase its rate of evaporation.

15.  When a molecule near the surface absorbs the
energy to overcome the vapour pressure, it will
escape and enter the surrounding air as a gas .
When evaporation occurs, the energy removed
from the vaporized liquid will reduce the
temperature of the liquid, resulting in
evaporative cooling.

16.  During summer , we perspire more because
this mechanism keeps our body cool.
 Cotton is a strong water absorber helps to
absorb the sweat and introduce to the
environment by evaporation. Our body takes
out heat as the sweat evaporates from our
body.

17.  Plasma – It consist of super energetic and
super excited particles. These particles are
in form of ionised gases. The fluorescent
tubes and neon sign bulbs consist of plasma .
When this gas gets ionised as if it get charged
this creates the glowing plasma.

18.  In 1920 , Indian physicist Satyendra Nath
Bose has done some calculations for fifth
state of matter on the basis of these
calculations Albert Einstein predicted a new
state of matter.