Study the Similarities and Differences Between Solids, Liquids, and Gases

The particle model

The particle model is the idea that everything is made of tiny 'building blocks' of matter called atoms. You may have learnt in chemistry lessons that more than one atom joined together is called a molecule. 

In physics, we use the term 'particle' to mean either atoms or molecules, so it is a general word for very small pieces of matter.

 

You need to know that solids, liquids, and gases are the three states of matter, and you also need to have an understanding of how the particles in each of these states behave.

 

Solids

 

  

 

The particles in solids are packed very close together. They each vibrate about a fixed position. The forces between the particles are very strong.

 

Liquids

 

 

The particles in a liquid are further apart and the forces between them are weaker. Instead of vibrating about fixed positions, the particles in a liquid move randomly. Fluids can fill the shape of any container as the particles are able to slide over each other. Notice that each particle is still in contact with another particle.

 

Gases

 

 

Finally, gas molecules are the fastest moving. They have very weak forces between them, and they also move randomly in all directions. Just like liquids, they can fill the shape of any container.

 

Now you know the difference between the three states of matter, you are ready to try some questions!