A building or house is constructed with the help of bricks, stones and other solid materials. And, the water we drink, the lake, and the sea are in the liquid form. Then, the air we breathe and the gases in our atmosphere are in a gaseous stage.
Therefore, generally, we can classify the matters into three types these are
Therefore, generally, we can classify the matters into three types these are
- Solid state
- Liquid state
- Gaseous state

States of matter
Solid state
The objects which have a definite shape, distinct boundaries and a fixed volume is called as solid objects, or they are in solid-state.
Example:
A book, pen, pencil.
A car, bike, plan, bus, etc.
The solid objects tend to stay on their original shape despite the external force.

Rocks
- Solids have definite shape and volume.
- The particles of solids are very closely packed and the interparticle attractions are very strong.
- The strong force of attraction hold the particles in fixed position, preventing them from moving freely.
- The particles do not have enough space to move from one place to another. Instead, they can only vibrate or oscillate about their fixed positions.
- The molecules inside the solids are so condensed, and this is the reason that they are rigid and maintain the definite shape
For example, if we apply external force to the piece of chalk, it will break into pieces, but the nature of the particles will not be altered as solids are rigid bodies.
Intermolecular Force on solids:
The intermolecular force in the solid is the strongest force compare to the liquid and gas. This strongest inter molecule force makes the solid matter denser and gives a certain shape and structure to it.

Interparticle spacing in solids
Effect of temperature on solids:
When a solid is heated, the particles absorb energy and the kinetic energy of the particles increases and begin to viberate vigorously. As the temperature increases the vibrations become so vigorous, and the particles overcome the interparticle forces of attraction get weakened and the solid gets converted into the liquid state.
The minimum temperature at which a solid melts to become a liquid at the atmospheric pressure is called the melting point.

Melting of ice cubes
The melting point of ice is .
Some solids have weak interparticle forces of attraction, so their melting points are low. While others have strong attractive forces and have high melting points.
Example:
i. Urea - \(133°C\)
ii. Iron - \(1538°C\)
Liquid state
In our day to day life, we come across many liquid state matters, such as the water we drink, the oil we use for cooking, the fruit juice we often drink, etc. These are all the matters in a liquid state.

Friut juices
Liquids do not have a certain shape, but it can take the shape of the container when we pour it in the container. For example, we might have seen the juice bottles. The liquid inside the bottle takes the shape of the bottle.
- An intermediate phase between the solid and gas.
- Liquids have a fixed volume but no fixed shape.
- Liquids take the shape of the container without changing their volume.
Intermolecular Force on Liquid:
Activity:
Take some water and try to move fingers throughout it. The fingers can be moved throught water without breaking or cutting it permanently, the same cannot be done in the case of solids.

Moving fingers through water
As soon as removing the finger the position of water is restored.
The interparticle force in liquid is not high as compared to solid, but still strong enough to keep the particles closer.

Interparticle space of states of matter
Effect of temperature on liquids:
When a liquid is heated, the kinetic energy of the particles increases and starts moving daster. As the temperature increases, the force of attraction between liquid particles decreases, allowing them to move more freely. Eventually, the constituent particles gain energy and the liquid is converted into vapour or the gaseous state.
The temperature at which a liquid begins to boil and turns into vapour at the atmospheric pressure is known as its boiling point.
Gaseous state
While your mother cooks in the kitchen, you can sense the delicious aroma coming to you even though you're in another room. Have you ever wondered how that smell came to you?
And, we all like balloons, right? But, have you ever wondered how the balloon seller fill those a large number of balloons in a short span of time? The answer is gases.

Gas characteristics
Gases are highly compressible as compared to solids and liquids. In the gaseous state, the particles move about randomly at high speed.
Because of this property, we can use the gases in LPG in highly compressed condition. If we compress the gas particles, we can store it in a small container too.
We know that gas particles have more freely movable particles, so it can travel through the air easily. That's why the aroma of a food reaches to you even though you're in a separate room.
Intermolecular force on gases:
The inter molecule force in the gaseous substance is weaker as compare to the liquid and solid. This weaker inter molecule force makes the gaseous matter to move freely in the air.

Interparticle spacing in gases
Transformation of states:
Have you ever wondered why ice turns into puddles of water on a sweltering day?
Knowing that matters can change its states; when a state change occurs, the properties of substances also change. Similarly, if the state change is reversed, the substance will recover the properties which it had before.

Transformation of states of matter
The matter changes its state respective to the energy applied to it. The following figure explains how the matter changes its state wherever the energy is applied.
Transformations of states
This leads to the rearrangement to the substance because the attracting force no longer holds the particles tightly.
Reference:
https://commons.wikimedia.org/wiki/File:VW_Fingers_touching_water.jpg
By Julio Miguel A Enriquez and Monica Muñoz - Wiki Learing Tec de Monterrey, CC BY-SA 4.0, Link