The Particle Model is a scientific idea used to explain the structure and behaviour of matter. It states that all substances are made of tiny particles—these can be atoms, molecules, or ions. The way these particles are arranged and how they move helps explain the three states of matter:
In a solid, particles are tightly packed in a fixed arrangement and vibrate in place.
In a liquid, particles are close together but can move past each other, so liquids can flow.
In a gas, particles are far apart and move quickly in all directions, filling the space around them.
The Particle Model helps explain physical changes like melting, boiling, and condensing, and is a key concept in GCSE Chemistry.
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