Matter exists in three different states in nature: solid, liquid and gas. These states are due to the constant movement of the particles, atoms or molecules, that make up matter, and to the stronger or weaker attraction between these particles. In a gas, particles move freely and attract each other very weakly. They are a long way apart. Gas fills all available space. In a liquid, the particles attract each other much more and even touch, but still move. In a solid, the particles attract each other strongly and move very little.
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