Explain the factors affecting diffusion and the state of particles in liquids and gases.

The conclusion is that the rate of diffusion increases with temperature. Particles in warmer water have more kinetic energy, causing them to move faster and spread the food colouring more quickly.

It is important to use the same amount of liquid in each beaker to ensure a fair test. This keeps the volume of the solvent (water) constant, so that any observed differences in diffusion rate can be attributed solely to the change in temperature, making the experiment reliable.

In a liquid state, particles are close together but randomly arranged. They are able to slide past one another, allowing liquids to flow and take the shape of their container.
A model representation would show:

• Many small circles (particles) clustered together.
• The circles should be touching or very close, but not in a rigid, ordered pattern.
• They should fill the bottom portion of a container, showing that liquids have a definite volume but no definite shape.

• Particle movement in gas (deodorant): Gas particles are far apart, move randomly and rapidly in all directions, and have high kinetic energy.
• Particle movement in liquid (juice in water): Liquid particles are closer together than gas particles, move randomly but slide past each other, and have less kinetic energy than gas particles.
• Diffusion speed: Gases diffuse much faster than liquids. The deodorant (gas) will spread its scent through the air almost instantly, while the juice (liquid) will take a noticeable amount of time to fully mix with the water. This is because gas particles have more space between them and move with greater speed.