International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

What is the relationship between particle movement and temperature?

1. Particle movement decreases as temperature increases

2. Particle movement increases with increasing temperature

3. Temperature has no effect on particle movement

4. Particle movement is constant regardless of temperature

The correct answer is: Particle movement increases with increasing temperature

Particle movement is directly related to temperature due to the kinetic theory of matter. As temperature increases, the average kinetic energy of the particles in a substance also increases. This results in more vigorous movement; particles move faster and farther apart from each other. In gases, for example, increased temperature leads to particles bouncing around with greater speed and energy, which can increase the pressure if the gas is contained. In liquids and solids, while particle movement is more restricted compared to gases, an increase in temperature causes particles to vibrate more and, in the case of liquids, to move more freely. This relationship is fundamental to understanding the behavior of different states of matter and their transitions, such as melting and boiling, which occur at specific temperatures due to the increased energy and movement of the particles.