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GAS: A gas is a sample of matter that conforms to the shape of a container in which it is held and acquires a uniform density inside the container, even in the presence of gravity and regardless of the amount of substance in the container.
Example: Air, oxygen, hydrogen.
Liquid: The state of matter in which a substance exhibits a characteristic readiness to flow and little or no tendency to disperse, and is amorphous but has a fixed volume and is difficult to compress.
Example: Water, Petrol
Solid: Solid is one of the four fundamental states of matter (the others being liquid, gas, and plasma). It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to each other.
Example: Coal, Rocks, Wood.
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