Particle Model - BBC Bitesize

You can use the idea of particles to explain the properties of solids, liquids and gases.The strength of bonds between particles is different in all three states. It explains why solids cannot flow, and why gases can be compressed.This Revision Bite covers: Solids LiquidsGasesFlowingArrangement and Movement

Solids Steel, plastic and wood are solids at room temperature. Ice is solid water. The particles in a solid have the following characteristics: they are arranged in a regular pattern they are close together they are held together by strong forces called bonds they can vibrate in a fixed position they cannot move from place to place The table shows some of the properties of solids and why they are like this.                 Property of solids                                Why they are like this  They have a fixed shape and cannot flow.     The particles cannot move from place to placeThey cannot be compressed or squashed.   The particles are close together and have no space to move into.

Liquids Mercury, lemonade and water are liquids at room temperature. The particles in a liquid are: close together arranged in a random way The particles in a liquid can: move around each other The bonds in a liquid are strong enough to keep the particles close together, but weak enough to let them move around each other. The table shows some of the properties of liquids and why they are like this. Property of liquids Why they are like this They flow and take the shape of their container.  The particles can move around each other. They cannot be compressed or squashed. The particles are close together and have no space to move into. 

Gases 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. 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.

Arrangement and movement The table summarises the arrangement and movement of the particles in solids, liquids and gases. It also shows simple diagrams of the arrangement of the particles that you should be able to draw and recognise.   Solid Liquid Gas Arrangement of particles Close togetherRegular pattern Close togetherRandom arrangement Far apartRandom arrangement Movement of particles Vibrate on the spot Move around each other Move quickly in all directions Diagram

Introduction

Solids

Liqiuds

Gases

Arangement and Movement