a) States of matter
1.1 Understand the arrangement, movement and energy of the particles in each of the three states of matter: solid, liquid and gas
Solids - All of the particles in a solid are touching. The particles have so little energy so do not move very much at all.
Liquids - Liquid particles, like solids, are touching. However the particles are moving and have some energy.
Gas - In Gases the particles are far apart. They move freely and faster than liquid particles so have some energy.
1.2 understand how the interconversions of solids, liquids and gases are achieved and recall the names used for these interconversions.
Solid > Liquid
This process is called melting: you apply heat.
Liquid > Solid
This is freezing. You remove heat.
Liquid > Gas
Heat is added. The process is evaporation.
Gas > Liquid
Removed heat: condensing.
1.3 explain the changes in arrangement, movement and energy of particles during these interconversions.
Solid: still; no energy; all particles touching
Add heat v / Remove heat ^
Liquid: Moving to fit space; some energy; all particles touching
Add heat v / Remove heat ^ b) Atoms
1.4 describe and explain experiments to investigate the small size of particles and their movement including: i dilution of coloured solutions ii diffusion experiments
Dilution: a substance is put in a solvent to reduce its concentration
Diffusion: The movement of particles from an area of high concentration to an area of low concentration
Experiment 1, Diffusion
Hydrochloric acid is placed at one end of a tube, ammonia solution at the other.
Where they meet a ring of ammonium chloride appears.
The diagram shows it is closer to the ammonia solution.
From this we can tell that ammonia must have travelled faster, as it got further in the time. Lighter particles travel faster- so we can tell that ammonia is a lighter gas. Experiment 2, Dilution Put a coloured substance in a solvent e.g food colouring in water.
You can see that over time the colour levels out but is weaker than the original colour- this is dilution.
Dilution at different temperatures: more heat; means more energy; means more movement; so the particles can move to different areas more quickly. So applying heat decreases the amount of time taken for the coloured substance to be fully diluted.
1.5 understand the terms atom and molecule
An atom is made up of a nucleus (protons…