Gases
Science: KS3, topic 3.5.13
Gases
Gases are one of the main three states of matter. Gases are useful because their properties mean they can be stored under pressure.
Particle arrangement
- Particles in gases are not close together.
- The particles are far apart from each other.
- The forces between the particles are very weak.
- The particles can be compressed.
Movement
- The movement of the particles is totally random.
- Particles in gases have lots of energy.
- The particles move quickly.
- Gases will completely fill their container.
Density
- Gases are not very dense because of the large spaces between the particles.
Temperature
- If the temperature rises, particles gain more energy.
- So the particles move faster and faster.
- Faster particles raise the pressure.
- Particles hit the container walls more often.
Test yourself on Gases
Why do gases have a low density?
A student says that a gas exerts pressure on a container because of the particles colliding with one another in the container, and the particles colliding with the walls of the container. Are they correct? Explain your reasoning.
What happens to a balloon if the temperature of the gas inside it increases?
Two identical sealed containers hold the same gas. One container is heated and the other is kept at room temperature. Which container has the higher gas pressure?