A gas is stored in a sealed container of constant volume. The temperature of the gas increases. This causes the pressure of the gas to increase. What happens to the kinetic energy of the gas molecules during this pressure increase?

An engineer wants to fix a steel washer on to a steel rod. The rod is just too big to fit into the hole of the washer. How can the engineer fit the washer on to the rod?

Why are the cables left loose?

What is the main process by which the water at the bottom of the glass becomes cool?

Between which labelled points on the graph is the substance partly solid and partly liquid?

Molecules escape from a liquid during evaporation. The temperature of the remaining liquid changes. Which molecules escape and how does the temperature change?

The diagram represents moving gas molecules in a sealed container of fixed volume. The temperature of the gas is now increased. What happens to the pressure of the gas, and what happens to the speed of the gas molecules?

The diagrams show four blocks of steel. The blocks are all drawn to the same scale. The same quantity of thermal energy (heat) is given to each block. Which block shows the greatest rise in temperature?

Which two beakers should she use to check the fixed points?

The gas in a container is heated but is kept at constant volume. Why does the gas pressure increase?

Small smoke particles suspended in air are viewed through a microscope. The smoke particles move randomly. What does this show?

A substance loses thermal energy (heat) to the surroundings at a steady rate. The graph shows how the temperature of the substance changes with time. What could the portion PQ of the graph represent?