MATTER IN OUR SURROUNDINDS

    

BOARD: NCERT

STANDARD: 9TH

SUBJECT:SCIENCE

CHAPTER: 1

                                                                                                                                                                      

                                         MATTER IN OUR SURROUNDINGS

PHYSICAL NATURE OF MATTER

    Matter is made up of particle

    Particles of matter a very small

CHARACTERISTICS OF PARTICLE OF MATTER

   

    Particles of matter have space between them: Particles of one type of matter get into the spaces between particles of the other. This shows that there is enough space between particles of matter.

    Particles of matter are continuous moving:   As the temperature rises, particles move faster.

                  => Temperature is proportional to  Kinetic energy of particles

    Particles of matter attract each other: particles of matter have force acting between them. This force keeps the particles together. The strength of this force of attraction varies from one kind of matter to another.

STATES OF MATTER

 Matter around us exists in three different states;

                                                               Solid

                                                               Liquid

                                                               Gas

 These states of matter arise due to the variation in the characteristics of the particles of matter.

    Solid: Solids have a tendency to maintain their shape when subjected to outside force. Solids may break under force but it is difficult to change their shape, so they are rigid.

•  definite shape
•  fixed volume
•  distinct boundaries

    Liquid: They take up the shape of the container in which they are kept. Liquids flow and change shape, so they are not rigid but can be called fluid.

• no shape
• fixed volume                                                                                                                                     => The rate of diffusion of liquids is higher than that of solids.  

     Gaseous:  particles move about randomly at high speed. Due to this random movement, the particles hit each other and also the walls of the container.

• highly compressible
• moves in high speed

MATTER CHANGE ITS STATE

       Pressure and Temperature determine the state of a substance. we can change the state by changing the pressure and temperature.

we can understand this through a simple concept map given bellow;