Cambridge Secondary (7-9). Stage 8. Science. Learner's Book - Unit 3: Forces and energy - Question 124

Part 2: Pressure and temperature in gases. In this activity, you will observe the effect of changing temperature on the pressure in a gas. Work in groups of two or three. You will need: empty plastic bottle (0.5–2 litre) with lid; access to a warm place; access to a cold place, such as a refrigerator. Method: 1 Take the lid off the bottle. 2 Leave the bottle and the lid in a warm place for 5–10 minutes. 3 Put the lid tightly on the bottle without squeezing the bottle. Do this while the bottle is still in the warm place. 4 Put the bottle into a cold place for 15–20 minutes. 5 Observe what has happened to the bottle.

Explain your answer to 5.