Today we are going to learn important concept of lesson Matter In Our Surroundings.In this topic we shall learn different types of matter and their characteristics.
⚫What is matter?
Anything that occupies space and has a mass is called matter. Matter can be also felt by senses.
Example: table, fan, chair, chalk, blackboard etc.
Table of Contents
⚫What are the characteristics of matter?
✔️They have very tiny particles.
✔️Particles of matter are always in continuous motion.
✔️Particles have vacant spaces,
✔️ Particles are held by the force of attraction.
⚫What are the different states of matter?
Based upon the particle arrangements matters are classified into the following types.
✔️Solid
✔️Liquid
✔️Gas
✔️Plasma
✔️Bose Einstein condensate
⚫Solid state
✔️They have fixed boundary.
✔️Their constituent particles are very closely packed in solid state.
✔️They have fixed shape and definite volume.
✔️They cannot be compressed means they are incompressible.
✔️The intermolecular force of attraction is a very high.
✔️They have high density.
✔️They can not diffuse.
✔️They have high rigidity.
✔️The intermolecular distance between the particles are very less.
⚫Liquid state
✔️They are fluid.
✔️They do not have fix boundary.
✔️Their constituent particles are less closely packed.
✔️They do not have fixed shape but they have fixed volume.
✔️They are almost incompressible.
✔️The intermolecular forces of attraction between the particles are weaker than solid state.
✔️They have lower density than the solid state.
✔️They can diffuse.
✔️The interparticle distances between the particles are larger than the solid state.
⚫Gaseous state
✔️They do not have fixed boundary.
✔️Constituent particles are free to move.
✔️They have neither fixed shape nor fixed volume.
✔️They are highly compressible.
✔️The intermolecular forces of attraction between the particles are least.
✔️Their density are least.
✔️The ycan diffuse easily.
✔️The interparticle distances between the particles are more than solid and liquid.
⚫Plasma state
✔️They are ionized gas.
✔️They are good conductor of electricity.
✔️They are affected by magnetic fields.
✔️Plasma gases have an indefinite shape and indefinite volume.
⚫Bose Einstein condensate
✔️BEC is a state of matter that can arise at very low temperatures.
✔️The BEC is all about molecules that are really close to each other even closer than atoms in a solid
⚫Why solid have definite shape?
Solids have definite shape because the particles of solids are closely packed.
⚫Why solids do not flow like liquid?
The particle of solids are very close to each other. There are no available space between the particles. That’s why solid do not flow like liquids.
⚫Solids are not compressible?
Because there is no available space between the particles.
⚫Liquids can flow easily?
Liquids can flow easily because there is a space between the particles.
⚫Liquids have in definite shape but definite volume?
There is a little space between the liquid particles. They Can acquire the shape of container in which they are placed. Therefore Liquid have indefinite shape but definite volume
⚫Why gases can flow easily?
Gases can flow easily because the interparticle distance between the particles are more . And force of attraction between the particles are least.
⚫ Why gases are compressible?
Because there is a great space between the particles of gases.
⚫ Why gas have in definite shape and indefinite volume?
Gases have different shape and in different volume because the particles can move anywhere .
⚫Interchange in State of matter
By heating the matter or removing the heat from the matter matter can be converted into the different forms.
✔️Solid to liquid
✔️Liquid to gas
✔️Solid to gas
By removing the heat or cooling the matter
✔️Gas to liquid
✔️Liquid to solid
✔️Gas to solid
⚫Solid to liquid (melting)
The process in which a solid substances changes into a liquid on heating is called melting or fusion.
When ice changes into water on heating it is called melting of ice or fusion of ice.
the temperature at which a solid substance melts and changes into the liquid at atmospheric pressure is called melting point of the substances.
⚫Liquid to gas (boiling or vaporization)
The process in which liquid gets converted to the gas by rapid heating is called boiling.
When water changes into the gas it is called as boiling of water.
At the temperature at which liquid boils and changes rapidly into the gas at atmospheric pressure is called boiling point of liquid.
When water is heated upto 100 degree Celsius it started converting into the steam rapidly. Boiling point of water is 100 degree Celsius.
⚫Solid to gas or gas to solid (sublimation)
Solid on heating directly gets converted into the gas without going into the liquid state is called sublimation.
Or sometime gas on cooling directly it’s converted to the solid state is also known as sublimation process.
Examples
camphor, ammonium chloride, iodine undergoes sublimation process.
⚫Gas to liquid (condensation)
The process of changing a gas into liquid by cooling is called condensation.
When gas(water steam) is cooled or heat is removed it start forming water droplets this process is called as condensation.
Condensation is the reverse process of boiling or vaporization.
⚫Liquid to solid (freezing)
The process in which liquid gets converted into the solid by cooling is called freezing.
For example
when water is called it gets converted into the solid that is called as ice. This is called freezing of water and freezing means solid formation.
Freezing is reverse of melting.
The temperature at which liquid gets converted into the solid by cooling is called freezing point of liquid.
⚫Latent heat
The heat energy which has to be supplied to change the state of a substance is called its latent heat.
Latent heat does not raise or increase the temperature.
There are two type of latent heat
⚫Latent heat of fusion
The latent heat of fusion or melting of a solid is the quantity of heat in joules required to convert 1 kg of solid at its melting point to a liquid without any change in temperature.
⚫Latent heat of vaporization
Latent heat of vaporization of liquid is the quantity of heat in joules required to convert 1 kg of liquid at its boiling point to vapour or gas base without any change in the temperature.
⚫Effect of change of pressure
The physical state of matter can also be changed by changing the pressure. Changing the pressure means either increasing the pressure or decreasing the pressure.
For gaseous state when the pressure is applied and temperature is lowered the gas can be converted into to liquid form. Liquefaction of gas is done by applying the high pressure and lowering the temperatures.
For example
Oxygen gas can be liquefied by applying the high pressure and lowering the temperature.
⚫What is evaporation ?
It is the process of liquid changing into the vapour or gas even below its boiling point.
⚫ Factor affecting the evaporation ?
Surface area
Rate of evaporation increases on increasing the surface area of the liquid
Temperature
Rate of evaporation also increases on increasing the temperature of liquid.
Humidity
When the humidity present in the air is low then the rate of evaporation is high and water evaporates more rapidly.
And when the humidity of air is higher than the rate of operation is slow and the water evaporate very slowly.
Wind speed
When wind speed increases the rate of evaporation of liquid also increases.
