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Particle model



Air, helium and chlorine are gases at room temperature. Water vapour is water as a gas.

The particles in a gas are:

  • far apart

  • arranged in a random way

The particles in a gas can:

  • move quickly in all directions

There are no bonds between the particles in a gas, so they are free to move in any direction.

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The table shows some of the properties of gases and why they are like this.

Property of gases Why they are like this
They flow and completely fill their container. The particles can move quickly in all directions.
They can be compressed or squashed. The particles are far apart and have space to move into.


The particle model activity

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