Pearson Edexcel International GCSE (9–1) · PHYSICS · Section
The energy involved in change of state
17 practice questions
Practice questions
1–7 of 7 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State what happens to the temperature of a substance during melting, while it is still being heated.
Question 2
1 mark · Easy
Answer and check →Which of the following best describes what happens to the energy supplied to a substance at its boiling point?
- A.It is used to raise the temperature further.
- B.It is used to increase the mass of the substance.
- C.It is used to overcome the forces between molecules.
- D.It is used to break the bonds inside the molecules.
Question 3
2 marks · Easy
Answer and see the solution →Describe what a temperature–time graph would look like for a substance that is being heated steadily as it melts from solid to liquid.
Question 4
2 marks · Easy
Answer and see the solution →Explain why the temperature of a substance does not change during boiling, even though energy is still being supplied.
Question 5
2 marks · Easy
Answer and see the solution →A student heats a solid and records its temperature every minute. Describe how the temperature readings would change if the student continues heating the substance until it has fully melted and then further increases the temperature.
Question 6
3 marks · Easy
Answer and see the solution →A student wants to demonstrate how the temperature of stearic acid (a solid) changes as it melts and then becomes a liquid.
(a)[1 mark]Describe one safety precaution the student should take while heating stearic acid.
(b)[2 marks]Explain what happens to the temperature of stearic acid as it is heated, melts, and then is fully in liquid form.
Question 7
2 marks · Easy
Answer and see the solution →A scientist records the temperature of a pure substance as it is heated steadily. The measured values are shown in the table below.
Temperature vs Time for a Substance being Heated Time (min) Temperature (°C) 0 20 2 40 4 60 6 80 8 80 10 100 Explain what the constant temperature at 80 °C from 6 to 8 minutes shows about what is happening to the substance.