Solid Liquid and Gases Multiple Choice Questions and Answers

11. Particles have random motion. This means

1. the particles always travel in straight lines
2. the particles stand still
3. the path of the particles cannot be predicted
4. the path of the particles are curved

12. When an iron bar is heated it gets longer. This is because the particles in the bar

1. change shape
2. get bigger
3. get closer together
4. move further apart