Everything in our surroundings comprises “matter”.
- The matter is anything that has mass and occupies space (has volume).
- The matter is classified based on its PHYSICAL and CHEMICAL properties
PHYSICAL PROPERTIES OF MATTER
- Matter exists in the form of particles.
- these particles are very small in size
- CHARACTERISTICS OF PARTICLES OF MATTER
- Particles of matter have space between them.
- Particles of matter are in continuous motion. They possess kinetic energy.
- Particles of matter attract each other.
The variation in these characteristics of the matter is responsible for the state of matter, i.e. the character of these particles at a given time decides in what state the matter will exist, either solid, liquid or gas.
THE STATES OF MATTER
Matter generally exists in three different states:
The particles of solids have a high force of attraction and as the force of attraction between the particle is high so the particles remain closely bound and the force of attraction overcomes the kinetic energy of the particles so they only vibrate at their position. These characteristics of the particle give solids:-
- Definite shape
- Definite volume
- Non-compressible nature
- They cannot flow, i.e. are not fluid.
The particles of liquids have the force of attraction less than that of solids and as the force of attraction between the particle is less so the particles are apart from each other and the force of attraction cannot completely suppress the kinetic energy of the particles so they are free to move inside the liquid. Because of these characteristics of the particles liquids, liquids have:-
- Definite volume
- No definite shape,
- Compressible nature
- Fluid nature
The particles of gases have the least force of attraction and as the force of attraction between the particle is less so the particles are free to move from and the force of attraction cannot suppress the kinetic energy of the particles so they occupy the whole space available to them. Because of these characteristics of the particles gases, gases have:-
- No definite
- No definite volume
- Are highly compressible
- Are fluid
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