AQA GCSE Combined Science: Trilogy Physics Paper 1 (Foundation), November 2020: Question 4

13 marks · Low Demand difficulty · Short Answer

Answer questions on the particle model, temperature, changes of state, specific heat capacity, and latent heat of vaporisation using data from cooling a balloon in liquid nitrogen.

Practise this question

Question

Question 4 consists of eight parts (04.1 to 04.8). 04.1 asks how air particles move with four tick-box choices. 04.2 shows illustrations of three thermometers (a liquid-in-glass thermometer reading from -40 to 30 °C, a probe thermometer with range 10 to 300 °C, and a digital sensor thermometer with range -200 to +200 °C) and asks which can measure the temperature of liquid nitrogen at -196 °C. 04.3 asks to suggest why insulating gloves are worn. 04.4 asks to complete sentences describing particle speed and kinetic energy as air cools, using words from a box: decreased, stayed the same, increased. 04.5 gives air mass (0.00320 kg), temperature decrease (215 °C), and thermal energy change (860 J), asking to calculate the specific heat capacity. 04.6 asks what happens to temperature as nitrogen boils (multiple choice). 04.7 asks for the definition of vaporisation (multiple choice). 04.8 gives vaporised nitrogen mass (0.0072 kg) and energy transferred (1440 J) to calculate specific latent heat of vaporisation.
Question text

04 A scientist had a balloon which was filled with air.

04.1 Which statement describes how air particles move?

[1 mark]

Tick ( ) one box.

At random speeds in random directions

At random speeds in the same direction

At the same speed in random directions

At the same speed in the same direction

The temperature of the air was 19 °C

The scientist dipped the balloon into liquid nitrogen.

The temperature of the liquid nitrogen was −196 °C

04.2 Which thermometer could be used to measure the temperature of the liquid nitrogen?

[1 mark]

Tick ( ) one box.

04.3 The scientist wore special insulating gloves when putting the balloon into the

liquid nitrogen.

*14* Suggest why.

[1 mark]

04.4 When the balloon was put into liquid nitrogen the temperature of the air in the

balloon decreased.

Complete the sentences.

Choose answers from the box.

Each answer may be used once, more than once or not at all.

[2 marks]

decreased stayed the same increased

As the air in the balloon cooled down, the speed of the particles

. This is because the kinetic energy of the

particles 16 .

04.5 The air in the balloon had a mass of 0.00320 kg

The temperature of the air in the balloon decreased by 215 °C

The change in thermal energy of the air in the balloon was 860 J

Calculate the specific heat capacity of the air in the balloon.

Use the Physics Equations Sheet.

[3 marks]

Specific heat capacity = J/kg°C

04.6 The liquid nitrogen boiled.

What happens to the temperature of nitrogen as it boils?

[1 mark]

Tick ( ) one box.

Temperature decreases

Temperature increases

Temperature stays the same 17

The scientist recorded measurements to calculate the specific latent heat of

vaporisation of nitrogen.

04.7 What is meant by vaporisation?

[1 mark]

Tick ( ) one box.

A change of state from liquid to gas

*16* A change of state from solid to gas

A change of state from solid to liquid

04.8 The mass of nitrogen that vaporised was 0.0072 kg

1440 J of energy was transferred to the nitrogen as it vaporised.

Calculate the specific latent heat of vaporisation of nitrogen.

Use the Physics Equations Sheet.

[3 marks]

Specific latent heat of vaporisation = J/kg

Mark scheme

Show the mark scheme Mark scheme for question 04: 04.1: 'at random speeds in random directions' (1 mark). 04.2: 3rd thermometer ticked (1 mark). 04.3: 'to prevent (frost/cold) burns' or 'to prevent injury from the cold nitrogen', allow 'frostbite' (1 mark). 04.4: 'decreased', 'decreased' (2 marks). 04.5: Substitution 860 = 0.00320 × c × 215, rearrangement c = 860 / (0.00320 × 215), answer 1250 (J/kg°C) (3 marks). 04.6: 'temperature stays the same' (1 mark). 04.7: 'a change of state from liquid to gas' (1 mark). 04.8: Substitution 1440 = 0.0072 × L, rearrangement L = 1440 / 0.0072, answer 200 000 (J/kg) (3 marks). Total marks: 13.

AO /

Question Answers Extra information Mark

Spec. Ref.

04.1 at random speeds in random 1 AO1

directions 6.3.3.1

04.2 3rd thermometer ticked 1 AO2

6.3.2

04.3 to prevent (frost/cold) burns allow to prevent frostbite 1 AO3

6.3.2.2

or

to prevent injury from the cold

nitrogen

04.4 decreased 1 AO1

6.3.2.1

decreased 1 6.3.3.1

04.5 860 = 0.00320 × c × 215 1 AO2/1

860 4-5

c =

0.00320 × 215 1

6.3.2.2

c = 1250 (J/kg°C) 1 6.1.1.3

04.6 temperature stays the same 1 AO2

6.3.2.3

04.7 a change of state from liquid to 1 AO1

gas 6.3.2.3

04.8 1440 = 0.0072 × L 1 AO2

6.3.2.3

1440 1

L =

0.0072

L = 200 000 (J/kg) 1

Total 13

How to answer it

Particle Motion, Specific Heat Capacity & Latent Heat

📌 What this question tests

This question assesses fundamental ideas from the Particle Model of Matter (AQA Topic 3 / Paper 1):

  • Describing the movement and energy of gas particles as temperature changes.
  • Selecting suitable laboratory instruments based on measurement ranges (negative temperatures).
  • Identifying risks and safety precautions with extreme cryogenic temperatures.
  • Calculating specific heat capacity ( ΔE = m c Δθ ) and rearranging formulas.
  • Understanding temperature constancy during phase changes (boiling/vaporisation).
  • Calculating specific latent heat ( E = m L ).

Question 04.1: Motion of Gas Particles (1 Mark)

✅ Correct Answer

Tick box 1: At random speeds in random directions

💡 Key Knowledge

Gas particles move completely randomly. They collide elastically with each other and the container walls, leading to a wide spread of velocities.

🎯 Mark Scheme: 1 mark for selecting "at random speeds in random directions". Any other ticked option gives 0 marks.

Question 04.2: Selecting the Correct Thermometer (1 Mark)

✅ Correct Answer

Tick the 3rd thermometer (Digital probe thermometer with range -200 °C to +200 °C ).

🧠 Exam Technique: Range Check

Liquid nitrogen boils at -196 °C .

  • Thermometer 1 only goes down to -40 °C.
  • Thermometer 2 only goes down to +10 °C.
  • Only Thermometer 3 includes -196 °C inside its scale!
🎯 Mark Scheme: 1 mark for ticking the 3rd box only.

Question 04.3: Cryogenic Safety Precaution (1 Mark)

✅ Correct Answer

  • To prevent frostbite
  • OR To prevent (cold/frost) burns
  • OR To prevent injury from the extreme cold

❌ Common Errors

Saying "to keep hands warm" is too vague and does not gain credit. You must specify avoiding injury, severe tissue damage, or frostbite caused by extreme low temperature.

🎯 Mark Scheme: 1 mark for stating protection against extreme cold injury or frostbite.

Question 04.4: Temperature and Kinetic Energy (2 Marks)

✅ Correct Answers

As the air in the balloon cooled down, the speed of the particles decreased.

This is because the kinetic energy of the particles decreased.

💡 Key Knowledge

Temperature is directly proportional to the average kinetic energy of the particles. When cooled, particles lose kinetic energy and therefore slow down.

🎯 Mark Scheme: 1 mark for each correct word in place (both are decreased). Total: 2 marks.

Question 04.5: Specific Heat Capacity Calculation (3 Marks)

📐 Step-by-Step Calculation

  1. Select formula:
    ΔE = m × c × Δθ
  2. Substitute values:
    ΔE = 860 J
    m = 0.00320 kg
    Δθ = 215 °C
    860 = 0.00320 × c × 215 [1 mark]
  3. Rearrange for c:
    c = 860 / (0.00320 × 215)
    c = 860 / 0.688 [1 mark]
  4. Final Answer:
    c = 1250 J/kg°C [1 mark]

❌ Common Errors

  • Bracket mistakes: Typing 860 / 0.00320 × 215 into a calculator without brackets gives an impossible answer of 57,781,250!
  • Always multiply the denominator first: 0.00320 × 215 = 0.688 , then divide: 860 / 0.688 = 1250 .
🎯 Mark Scheme: 1 mark for substitution, 1 mark for rearrangement, 1 mark for correct value (1250). Full 3 marks awarded for correct answer alone.

Questions 04.6 & 04.7: State Changes & Vaporisation (2 Marks)

✅ 04.6 Boiling Temperature (1 Mark)

Tick box 3: Temperature stays the same

Reason: During boiling, thermal energy is used to break intermolecular bonds rather than increase kinetic energy.

✅ 04.7 Meaning of Vaporisation (1 Mark)

Tick box 1: A change of state from liquid to gas

Recall: Solid to gas is sublimation; solid to liquid is melting.

🎯 Mark Scheme: 1 mark each for the correct ticked options.

Question 04.8: Specific Latent Heat Calculation (3 Marks)

📐 Step-by-Step Calculation

  1. Select formula:
    E = m × L
  2. Substitute given numbers:
    E = 1440 J
    m = 0.0072 kg
    1440 = 0.0072 × L [1 mark]
  3. Rearrange for L:
    L = 1440 / 0.0072 [1 mark]
  4. Calculate value:
    L = 200 000 J/kg (or 2.0 × 10⁵ J/kg ) [1 mark]

🧠 Exam Technique: Choose the Right Equation!

Students often mix up the two thermal equations:

  • Temperature change? Use ΔE = m c Δθ (uses specific heat capacity).
  • State change at constant temp? Use E = m L (uses specific latent heat).
🎯 Mark Scheme: 1 mark for substitution, 1 mark for rearrangement, 1 mark for calculation (200 000). Total: 3 marks.

Topics

Physics · P1: Energy · P3: Particle Model of Matter

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Physics Paper 1 (Foundation), November 2020. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.