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Year 7 KS3

Particle     model

Everything in this world is made of particles. The smallest bacteria, there are over 1,000,000,000,000 atoms. In a normal glass of water, there are over 8,400,000,000,000,000,000,000 particle.

Have you ever looked at the back of a coke can?
What you’ll see is a bunch of chemicals. Food colouring, sugar substitutes, Acesulfame potassium, Aspartame, Citric Acid, Sodium Benzoate, Aroma additives and many others. Coke is a mixture, because it contains many different types of substances.

If we look at water tho, its only water molecules in side. This means water is a Substance. Something with only one type of particle in it, is called a substance.

Water, Gold, Oxygen are all substances.

Do some research and group the following into Mixtures or Substances and state what they are made of. For example, water is a substance and is made of H2O molecules.

You would have noticed, how water and ice look and act very different, but are made of the same molecules.

We can pour water, but we can’t pour ice.

This is due to how the molecules are arranged. The way we arranged molecules can have a huge effect on the end product.

Look at a diamond. Notice its properties. Its hard and shiny. Now look at the lead in your pencil. It’s dull and soft. This isn’t actually made of lead its real name is Graphite, and its made of the same thing as diamond.

 
Both diamonds and Graphite are made of Carbon atoms, its just how these atoms are arranged, that give them such different properties.

Click here to learn more about the states of matter

The kinetic Molecular theory states

1. All matter is composed of tiny particles

2. These particles are in constant motion

3. The amount of motion is proportional to temperature. Increased temperature means increased motion

4. Solids, liquids and gases differ in the freedom of motion of their particles and the extent to which the particles interact.

States of matter  Melting and Freezing  Graph analysis  Diffusion  Gas Pressure