Thermal properties and temperature — Paper 3 · IGCSE Physics 0625

5 (a) Fig. 5.1 shows a tank used for evaporating salt solution to produce crystals. For Examiner’s Use evaporating tank steam in salt solution steam out Fig. 5.1 Suggest two ways of increasing the rate of evaporation of the water from the solution. Changes may be made to the apparatus, but the rate of steam supply must stay constant. You may assume the temperature of the salt solution remains constant. 1. … … 2. … … [2] (b) A manufacturer of liquid-in-glass thermometers changes the design in order to meet new requirements. Describe the changes that could be made to (i) give the thermometer a greater range, … [1] (ii) make the thermometer more sensitive. … [1] (c) A toilet flush is operated by the compression of air. The air inside the flush has a pressure of 1.0 × 105 Pa and a volume of 150 cm3. When the flush is operated the volume is reduced to 50 cm3. The temperature of the air remains constant during this process. Calculate the new pressure of the air inside the flush. pressure = … [2]

6 marks

Mark scheme: 5 (a) increase surface area of tank B1 blow air over surface/put in windy place B1 2 (b) (i) capillary tube longer or liquid with lower expansivity B1 (ii) capillary tube thinner/finer or liquid with higher expansivity or bigger bulb B1 2 (c) p1v1 = p2v2 or 1 x 105 x 150 = p2 x50 C1 p2 = 3 x 105 (Pa) A1 2 [6]

This question in 0625/31 May/June 2006

4 Some water is heated electrically in a glass beaker in an experiment to find the specific heat For capacity of water. The temperature of the water is taken at regular intervals. Examiner’s Use The temperature-time graph for this heating is shown in Fig. 4.1. 60 temperature / °C 50 40 30 20 10 0 0 60 120 180 240 300 time / s Fig. 4.1 (a) (i) Use the graph to find 1. the temperature rise in the first 120 s, … 2. the temperature rise in the second 120 s interval. … (ii) Explain why these values are different. … … [2] (b) The experiment is repeated in an insulated beaker. This time, the temperature of the water increases from 20 °C to 60 °C in 210 s. The beaker contains 75 g of water. The power of the heater is 60 W. Calculate the specific heat capacity of water. specific heat capacity = … [4] (c) In order to measure the temperature during the heating, a thermocouple is used. For Draw a labelled diagram of a thermocouple connected to measure temperature. Examiner’s Use [2]

8 marks

Mark scheme: 4 (a) (i) 1 is 20°C 2 is 15 ± 1°C, need both correct for a mark A1 (ii) more heat lost at higher temperature B1 [2] (b) heat in = 60 x 210 or Wt or 12 600 (J) C1 heat in water = m x s x ∆θ or 75 x s x 40 C1 s = 12600/75 x 40 C1 = 4.2 J/g °C A1 [4] (c) outline correct, two wires with clear junction and a meter/datalogger/computer M1 labels, hot and cold junctions or clear, two different metals A1 [2] [Total: 8] IGCSE - OCT/NOV 2006 0625 03

This question in 0625/31 Oct/Nov 2006

10 Fig. 10.1 shows a circuit based on a transistor and a thermistor. power supply R2 R1 Fig. 10.1 (a) Describe the action of the thermistor in this circuit. … … … … [3] (b) State and explain how the circuit may be modified so that the lamp switches on at a different temperature. … … … [2] (c) State one practical use of this circuit. … [1]

6 marks

Mark scheme: 10 (a) when temperature rises resistance falls (or v.v.) M1 p.d. across it falls or equivalent (or v.v.) A1 idea of causes transistor to switch on lamp (or lamp off) A1 [3] (b) change value of R1/use variable res/swap R1 with something B1 brief explanation in terms of potential divider B1 [2] (c) fire alarm/refrigerator fail light/other automatic lighting system B1 [1] [Total: 6]

This question in 0625/31 May/June 2007

5 Fig. 5.1 shows some apparatus which is to be used to compare the emission of infra-red radiation from four differently painted surfaces. this side this side painted dull painted shiny white white water inlet metal box this side this side painted shiny painted dull black black Fig. 5.1 Near the centre of each side is an infra-red detector. The four detectors are identical. A supply of very hot water is available. (a) Describe how you would use this apparatus to compare the infra-red radiation from the four surfaces. … … … [3] (b) Suggest which surface will be the best emitter and which will be the worst emitter. best emitter … worst emitter … [1] (c) The infra-red detectors are made from thermocouples soldered to blackened metal plates. These are connected to galvanometers. In the space below, draw a labelled diagram of a thermocouple. [2] [Total: 6]

6 marks

Mark scheme: 5 (a) take readings of the detectors B1 fill box with water B1 take readings (again) B1 (b) dull black best AND shiny white worst B1 (c) two different metals B1 two junctions (could be at meter) hot and cold need not be indicated B1 any cell, max B1,B0 [Total: 6] IGCSE – October/November 2007 0625 03

This question in 0625/31 Oct/Nov 2007

2 (a) A certain volume of water at room temperature and the same volume of ice in a freezer For are each heated through the same temperature rise. Examiner’s Use Which of them will have the greater expansion, and why? Which? … Why? … [1] (b) For strength, concrete pillars are usually reinforced with metal rods, which are embedded in the concrete before it sets. The list below shows how much a length of 1 m of each material expands when the temperature rises by 1 °C. aluminium 0.03 mm concrete 0.01 mm steel 0.01 mm Use this information to decide which metal should be used to reinforce concrete, why it is suitable, and why the other metal is not suitable. Which metal should be used? … Why is it suitable? … Why is the other metal unsuitable? … … [3] [Total: 4]

4 marks

Mark scheme: 2 (a) water AND liquids expand more than solids B1 (b) steel M1 (steel) expands at same rate / has same expansion (as concrete) A1 different expansion AND cracks / breaks / damages / destroys concrete A1 [4]

This question in 0625/31 May/June 2009

7 Three wires and a meter are used to construct a thermocouple for measuring the surface For temperature of a pipe carrying hot liquid, as shown in Fig. 7.1. Examiner’s Use meter wire 1 wire 2 cold junction wire 3 hot junction hot liquid in pipe Fig. 7.1 (a) Copper wire and constantan wire are used in the construction of the thermocouple. State which metal might be used for wire 1 … wire 2 … wire 3 … [1] (b) State what type of meter is used. … [1] (c) State one particular advantage of thermocouples for measuring temperature. … [1] [Total: 3]

3 marks

Mark scheme: 7 (a) EITHER OR copper constantan copper constantan constantan copper B1 (b) galvanometer OR millivoltmeter OR milliammeter OR digital ammeter OR digital voltmeter B1 (c) rapid response ) small area ) can measure high / low temperatures ) small thermal capacity (idea of) ) any 1 B1 remote reading ) large range ) data logging / continuous monitoring possible ) takes temperature of a surface ) N.B. (very) sensitive not accepted [3]

This question in 0625/31 Oct/Nov 2009

9 (a) State what is meant by specific heat capacity. For Examiner’s … Use … [2] (b) Water has a very high specific heat capacity. Suggest why this might be a disadvantage when using water for cooking. … … [1] (c) Fig. 9.1 illustrates an experiment to measure the specific heat capacity of some metal. stirrer thermometer lid thread cup boiling water insulation metal water heater Fig. 9.1 The piece of metal is heated in boiling water until it has reached the temperature of the water. It is then transferred rapidly to some water in a well-insulated cup. A very sensitive thermometer is used to measure the initial and final temperatures of the water in the cup. specific heat capacity of water = 4200 J / (kg K) The readings from the experiment are as follows. mass of metal = 0.050 kg mass of water in cup = 0.200 kg initial temperature of water in cup = 21.1 °C final temperature of water in cup = 22.9 °C (i) Calculate the temperature rise of the water in the cup and the temperature fall of the piece of metal. temperature rise of water = … temperature fall of metal = … [1] (ii) Calculate the thermal energy gained by the water in the cup. State the equation For that you use. Examiner’s Use thermal energy gained = … [3] (iii) Assume that only the water gained thermal energy from the piece of metal. Making use of your answers to (c)(i) and (c)(ii), calculate the value of the specific heat capacity of the metal. Give your answer to 3 significant figures. specific heat capacity = … [2] (iv) Suggest one reason why the experiment might not have given a correct value for the specific heat capacity of the metal. … … [1] [Total: 10]

10 marks

Mark scheme: 9 (a) (quantity of) heat/energy to raise temp by 1 °C/1degC/1K/unit temp rise M1 1 kg OR 1 g OR unit mass (Mention of change of state gets M0 A0) A1 (b) long time to heat up/cook ) long time to cool down ) any 1 B1 expensive to heat ) takes a lot of energy to heat up ) (c) (i) 1.8 degC OR 1.8 °C OR 1.8 K AND 77.1 degC OR 77.1 °C OR 77.1K B1 (ii) (Q =) mcT in any form, seen anywhere B1 0.2 × 4200 × 1.8 e.c.f. from (c) (i) C1 1512 J (minimum 2 s.f.) c.a.o. A1 (iii) 1512 = 0.05 × c × 77.1 in any form e.c.f. from (c) (i) and/or (c) (ii) C1 392 J/kg K (N.B. must be to 3 sf ; A0 for wrong s.f.) e.c.f. A1 (iv) heat lost during transfer ) boiling water not at 100 °C / reason for not boiling at 100 °C e.g. water not pure/ not standard pressure ) energy lost to cup etc. / surroundings ) any 1 B1 thermometer not accurate / sensitive enough ) temperature / mass(es) not accurately measured ) [10]

This question in 0625/31 Oct/Nov 2009

7 Three wires and a meter are used to construct a thermocouple for measuring the surface For temperature of a pipe carrying hot liquid, as shown in Fig. 7.1. Examiner’s Use meter wire 1 wire 2 cold junction wire 3 hot junction hot liquid in pipe Fig. 7.1 (a) Copper wire and constantan wire are used in the construction of the thermocouple. State which metal might be used for wire 1 … wire 2 … wire 3 … [1] (b) State what type of meter is used. … [1] (c) State one particular advantage of thermocouples for measuring temperature. … [1] [Total: 3]

3 marks

Mark scheme: 7 (a) EITHER OR copper constantan copper constantan constantan copper B1 (b) galvanometer OR millivoltmeter OR milliammeter OR digital ammeter OR digital voltmeter B1 (c) rapid response ) small area ) can measure high / low temperatures ) small thermal capacity (idea of) ) any 1 B1 remote reading ) large range ) data logging / continuous monitoring possible ) takes temperature of a surface ) N.B. very sensitive or wtte not accepted [3]

This question in 0625/32 Oct/Nov 2009

9 (a) State what is meant by specific heat capacity. For Examiner’s … Use … [2] (b) Water has a very high specific heat capacity. Suggest why this might be a disadvantage when using water for cooking. … … [1] (c) Fig. 9.1 illustrates an experiment to measure the specific heat capacity of some metal. stirrer thermometer lid thread cup boiling water insulation metal water heater Fig. 9.1 The piece of metal is heated in boiling water until it has reached the temperature of the water. It is then transferred rapidly to some water in a well-insulated cup. A very sensitive thermometer is used to measure the initial and final temperatures of the water in the cup. specific heat capacity of water = 4200 J / (kg K) The readings from the experiment are as follows. mass of metal = 0.050 kg mass of water in cup = 0.200 kg initial temperature of water in cup = 21.1 °C final temperature of water in cup = 22.9 °C (i) Calculate the temperature rise of the water in the cup and the temperature fall of the piece of metal. temperature rise of water = … temperature fall of metal = … [1] (ii) Calculate the thermal energy gained by the water in the cup. State the equation For that you use. Examiner’s Use thermal energy gained = … [3] (iii) Assume that only the water gained thermal energy from the piece of metal. Making use of your answers to (c)(i) and (c)(ii), calculate the value of the specific heat capacity of the metal. Give your answer to 3 significant figures. specific heat capacity = … [2] (iv) Suggest one reason why the experiment might not have given a correct value for the specific heat capacity of the metal. … … [1] [Total: 10]

10 marks

Mark scheme: 9 (a) (quantity of) heat/energy to raise temp by 1 °C/1degC/1K/unit temp rise M1 1 kg OR 1 g OR unit mass (Mention of change of state gets M0 A0) A1 (b) long time to heat up/cook ) long time to cool down ) any 1 B1 expensive to heat ) takes a lot of energy to heat up ) IGCSE – October/November 2009 0625 32 (c) (i) 1.8 degC OR 1.8 °C OR 1.8 K AND 77.1 degC OR 77.1 °C OR 77.1K B1 (ii) (Q =) mcT in any form, seen anywhere B1 0.2 × 4200 × 1.8 e.c.f. from (c) (i) C1 1512 J (minimum 2 s.f.) c.a.o. A1 (iii) 1512 = 0.05 × c × 77.1 in any form e.c.f. from (c) (i) and/or (c) (ii) C1 392 J/kg K (N.B. must be to 3 sf ; A0 for wrong s.f.) e.c.f. A1 (iv) heat lost during transfer ) boiling water not at 100 °C / reason for not boiling at 100 °C e.g. water not pure/ not standard pressure ) energy lost to cup etc. / surroundings ) any 1 B1 thermometer not accurate / sensitive enough ) temperature / mass(es) not accurately measured ) [10]

This question in 0625/32 Oct/Nov 2009

11 Fig. 11.1 is an electronic circuit controlling an electric heater. For Examiner’s +5 V Use P electric Q relay coil heater 0 V a.c. Fig. 11.1 The relay contacts close when there is a current in the relay coil. (a) State the name of the logic gate in the circuit. … [1] (b) (i) State the name of component P. … [1] (ii) State what happens to P when its temperature falls. … [1] (c) For the relay to operate, the output of the gate must be high (logic 1). (i) What must be the input of the gate for the relay to operate? … [1] (ii) State what the resistance of P must be, compared with the resistance of Q, in order to give this input to the gate. … [1] (iii) Under what conditions will P have this resistance? … [1] (d) Suggest why component Q is a variable resistor, rather than one with a fixed value. … [1] (e) Suggest a practical use for this circuit. … [1] [Total: 8]

8 marks

Mark scheme: 11 (a) NOT or inverter B1 (b) (i) thermistor NOT thermal resistor B1 (ii) resistance increases OR voltage across it increases B1 (c) (i) LOW or 0 or off or NOT HIGH B1 (ii) (much) larger/ large / higher / high B1 (iii) low temperature e.c.f. from (c) (ii) B1 (d) to allow adjustment of the temp. at which relay will close / heater comes on B1 (e) automatic control or wtte of heating system / air-conditioning / automatic room heater OR thermostat OR any other sensible suggestion involving control of heating B1 [8]

This question in 0625/32 Oct/Nov 2009

4 A technician has been asked to design a liquid-in-glass thermometer, using alcohol as the For liquid. Examiner’s Use (a) (i) State what is meant by the sensitivity of the thermometer. … … [1] (ii) State one design feature the technician could use in order to ensure a very sensitive thermometer. … … [1] (b) (i) State what is meant by the range of the thermometer. … … [1] (ii) State one design feature that would ensure that the thermometer measured the desired range of temperatures. … … [1] (c) (i) State what is meant by linearity, as it applies to the thermometer. … … [1] (ii) State one design feature that would ensure linearity in the technician’s thermometer. … … [1] [Total: 6]

6 marks

Mark scheme: 4 (a) (i) change in length / distance moved (accept “how much it expands”) per unit / given temp rise OR equivalent B1 (ii) large bulb OR thin / narrow bore / tube / capillary NOT thin / narrow thermometer B1 (b) (i) difference between the highest and lowest temperatures ignore reference to fixed points B1 (ii) tube (sufficiently) long / not too short OR bore wide/not too thin OR little/not too much liquid/bulb NOT change liquid B1 (c) (i) idea of equal size divisions/expansion for equal temperature rises OR ∆l / ∆θ constant OR reference to l against θ graph straight line ignore 1 division = 1 °C B1 (ii) uniform bore OR alcohol/liquid expands uniformly (with temp) B1 [6] IGCSE – May/June 2010 0625 32

This question in 0625/32 May/June 2010

4 A technician has been asked to design a liquid-in-glass thermometer, using alcohol as the For liquid. Examiner’s Use (a) (i) State what is meant by the sensitivity of the thermometer. … … [1] (ii) State one design feature the technician could use in order to ensure a very sensitive thermometer. … … [1] (b) (i) State what is meant by the range of the thermometer. … … [1] (ii) State one design feature that would ensure that the thermometer measured the desired range of temperatures. … … [1] (c) (i) State what is meant by linearity, as it applies to the thermometer. … … [1] (ii) State one design feature that would ensure linearity in the technician’s thermometer. … … [1] [Total: 6]

6 marks

Mark scheme: 4 (a) (i) change in length / distance moved (accept “how much it expands”) per unit / given temp rise OR equivalent B1 (ii) large bulb OR thin / narrow bore / tube / capillary NOT thin / narrow thermometer B1 (b) (i) difference between the highest and lowest temperatures ignore reference to fixed points B1 (ii) tube (sufficiently) long / not too short OR bore wide/not too thin OR little/not too much liquid/bulb NOT change liquid B1 (c) (i) idea of equal size divisions/expansion for equal temperature rises OR ∆l / ∆θ constant OR reference to l against θ graph straight line ignore 1 division = 1 °C B1 (ii) uniform bore OR alcohol/liquid expands uniformly (with temp) B1 [6] IGCSE – May/June 2010 0625 33

This question in 0625/33 May/June 2010

4 A student in a laboratory uses the apparatus shown in Fig. 4.1 to determine the specific heat capacity of aluminium. to low voltage supply and measuring instruments thermometer electrical heater aluminium block Fig. 4.1 The readings obtained in the experiment are given below. mass of aluminium block = 0.930 kg initial temperature of block = 13.1 °C final temperature of block = 41.3 °C electrical energy supplied = 23 800 J (a) Define specific heat capacity. … … [2] (b) Use the readings above to calculate the specific heat capacity of aluminium. State the equation you use. specific heat capacity = … [3] (c) Because the student knows it is good scientific practice to repeat readings, after a short time he carries out the experiment again, supplying the same quantity of electrical energy. This time the temperature readings are: initial temperature of block = 41.0 °C final temperature of block = 62.1 °C (i) Use these figures to calculate a second value for the specific heat capacity of aluminium. specific heat capacity = … [1] (ii) The student did not make any mistakes when taking the readings. Suggest why the second value for the specific heat capacity of the aluminium is greater than the first. … … [2] (d) Suggest two ways of improving the experiment in order to give as accurate a result as possible. 1. … … 2. … … [2] [Total: 10]

10 marks

Mark scheme: 4 (a) heat/energy to raise/change temperature M1 of 1 kg/1g/unit mass through 1°C/1K A1 (mention of change of state scores zero) (b) Q = mcθ (for θ accept t, T, ∆θ, ∆t, or ∆T) B1 23800 = 0.93 × c × (41.3 – 13.1) C1 907.5 or 907 or 908 or 910 J/(kg °C) or J/(kg K) at least 2 sig. figs A1 (for unit in (b) and (c)(i) condone no brackets and extra solidus) (c) (i) 1212.9 or 1200 or 1210 or 1213 or 1214 J/(kg °C) or J/(kg K) B1 (ii) more energy lost (to surroundings) B1 (average) temperature is higher/initial temperature higher/no cooling time allowed/temperature rise is lower/time of heating may be longer/ rate of heating may be lower B1 (d) insulate block/provide lid/cover with shiny foil ) start & finish same amount below & above room temperature ) any 2 B1 + B1 get heater up to temperature before inserting ) put oil in gap between heater & block ) [Total: 10]

This question in 0625/31 Oct/Nov 2010

5 (a) Define specific heat capacity. … … [2] (b) Solar energy is striking the steel deck of a ship. (i) Describe how the colour of the deck affects the absorption of the solar energy. … … [1] (ii) The solar energy strikes the deck at the rate of 1400 W on every square metre. The steel plate of the deck is 0.010 m thick. Steel has a density of 7800 kg / m3 and a specific heat capacity of 450 J / (kg °C). 13% of the solar energy striking the deck is absorbed and the rest is reflected. Using these figures, calculate 1. how many joules of solar energy are absorbed by 1.0 m2 of the deck in 1.0 s, number of joules = … [1] 2. the mass of 1.0 m2 of deck, mass = … [2] 3. the rate of rise in temperature of the deck, stating the equation you use. rate of rise = … °C / s [3] [Total: 9]

9 marks

Mark scheme: 5 (a) heat/energy to raise/change temperature M1 of 1 kg/g/unit mass through 1°C/1K/unit temperature A1 (b) (i) darker colours absorb more OR lighter/shiny colours absorb less B1 (ii) 1. 182 B1 2. (mass of 1m2 =) volume × density OR D = M/V OR (1 ×) 0.01 × 7800 C1 78 kg A1 3. Q = mcθ B1 182 = 78 × 450 × θ (e.c.f. from 1,2) C1 0.00519 °C/s OR 5.19 × 10-3 °C/s (e.c.f. from 1,2) A1 [Total: 9] IGCSE – October/November 2010 0625 33

This question in 0625/33 Oct/Nov 2010

4 Use the information in the table when answering this question. specific heat capacity of ice 2.0 J / (g °C) specific heat capacity of water 4.2 J / (g °C) specific latent heat of fusion of ice 330 J / g specific latent heat of vaporisation of water 2260 J / g (a) Explain what is meant by the statement: ‘the specific latent heat of fusion of ice is 330 J / g’. … … … [1] (b) A block of ice is taken from a freezer at –25 °C, placed in a metal container, and heated by a source of constant power. The graph in Fig. 4.1 shows how the temperature of the contents of the container changes with time. At point E on the graph the container is empty. D E 100 temperature / °C 75 50 25 B C 0 time A –25 Fig. 4.1 (i) State what is taking place in the regions of the graph from B to C, and from D to E. B to C … … D to E … … [2] (ii) Use the information in the table to explain why the line DE is longer than the line BC. … … … [1] (iii) Use the information in the table to explain why the graph is steeper from A to B than from C to D. … … … [2] [Total: 6]

6 marks

Mark scheme: 4 (a) 330 J of heat / energy required to change 1 g of ice to water at constant temperature / at melting point / at 0 degrees C B1 (b) (i) (B to C ice is) changing to water / melting / changing to liquid / changing state B1 (D to E water is) changing to steam / vaporising / boiling / changing to gas B1 (ii) Sp. latent of vaporisation of water is greater than sp. latent of fusion of ice B1 (iii) s.h.c. of ice is less than s.h.c. of water B1 more heat required to raise temperature of water OR rate of temperature rise of water is slower OR temperature rise of water takes longer B1 [6]

This question in 0625/32 May/June 2011

4 Use the information in the table when answering this question. specific heat capacity of ice 2.0 J / (g °C) specific heat capacity of water 4.2 J / (g °C) specific latent heat of fusion of ice 330 J / g specific latent heat of vaporisation of water 2260 J / g (a) Explain what is meant by the statement: ‘the specific latent heat of fusion of ice is 330 J / g’. … … … [1] (b) A block of ice is taken from a freezer at –25 °C, placed in a metal container, and heated by a source of constant power. The graph in Fig. 4.1 shows how the temperature of the contents of the container changes with time. At point E on the graph the container is empty. D E 100 temperature / °C 75 50 25 B C 0 time A –25 Fig. 4.1 (i) State what is taking place in the regions of the graph from B to C, and from D to E. B to C … … D to E … … [2] (ii) Use the information in the table to explain why the line DE is longer than the line BC. … … … [1] (iii) Use the information in the table to explain why the graph is steeper from A to B than from C to D. … … … [2] [Total: 6]

6 marks

Mark scheme: 4 (a) 330 J of heat / energy required to change 1 g of ice to water at constant temperature / at melting point / at 0 degrees C B1 (b) (i) (B to C ice is) changing to water / melting / changing to liquid / changing state B1 (D to E water is) changing to steam / vaporising / boiling / changing to gas B1 (ii) Sp. latent of vaporisation of water is greater than sp. latent of fusion of ice B1 (iii) s.h.c. of ice is less than s.h.c. of water B1 more heat required to raise temperature of water OR rate of temperature rise of water is slower OR temperature rise of water takes longer B1 [6]

This question in 0625/33 May/June 2011

10 The circuit shown in Fig. 10.1 was designed by an electronics student to provide a warning, by sounding the buzzer, that there is light in a photographic darkroom at times when it is in use. buzzer + A 6 V logic – P C component gate Y switch X B R Q Fig. 10.1 When the darkroom is in use the switch is moved to position P. When it is not in use, the switch is in position Q. Depending upon the light level, the resistance of the light dependent resistor varies between much higher and much lower than the resistance of resistor R. (a) State what happens to the resistance of the light dependent resistor when the light level changes from dark to light. … … [1] (b) Write down whether the voltage level is high (logic 1) or low (logic 0) at the various points in the circuit in the following situations: (i) at A light in the darkroom, … dark in the darkroom, … (ii) at B switch in position P, … switch in position Q. … [2] (c) The output C of logic gate X is only high (logic 1) when both inputs A and B are high (logic 1). State which type of gate is logic gate X. … [1] (d) State the name of component Y. … [1] (e) Explain whether or not the student’s circuit achieves the aim of providing a warning that there is light in the darkroom when it is in use. … … … … [2] [Total: 7]

7 marks

Mark scheme: 10 (a) decreases / low / very low / zero B1 [1] (b) (i) ecf from (a), both answers must be consistent with candidate’s (a) B1 e.g. decreases / low / very low / zero increases / high / v. high / > 5V light high OR 1 light low OR 0 AND dark low OR 0 AND dark high OR 1 (ii) switch position P high OR 1 AND switch position Q low OR 0 B1 [2] (c) AND gate B1 [1] (d) transistor B1 [1] IGCSE – October/November 2011 0625 32 (e) any 2 of: (input) A high (input) B high C high transistor switches on/works M1 yes / it would work A1 [2]

This question in 0625/32 Oct/Nov 2011

11 (a) Describe the action of For Examiner’s (i) a NOT gate, Use … [1] (ii) a thermistor. … [1] (b) Fig. 11.1 shows a circuit that switches on a warning lamp when the temperature in an oven falls below a set value. thermistor warning P lamp R Fig. 11.1 Explain, with reference to the components in the circuit and point P, (i) why the warning lamp is on when the temperature in the oven is below the set value, … … … … … … … [4] (ii) the effect of changing the resistance of R. … … [1] [Total: 7]

7 marks

Mark scheme: 11 (a) (i) input high / on / 1, output low / off / 0 input low / off / 0, output high / on / 1 OR reverses / inverts state of input OR output opposite to input B1 (a) (ii) resistance changes as temperature changes B1 (i) at low temperature resistance of thermistor is high OR when temperature falls resistance of thermistor rises B1 p.d. across thermistor is high OR p.d. across R is low B1 (voltage) input to gate is low B1 output of gate is high (and warning light is on) B1 (ii) changes the temperature / set value at which the lamp comes on B1 [Total: 7]

This question in 0625/31 Oct/Nov 2013

1 (a) Fig. 1.1 shows a liquid-in-glass thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 1.1 (i) In the process of making the thermometer, the scale divisions were spaced equally. What assumption was made about the liquid? … … [1] (ii) Suggest two changes to the thermometer that would require the spacing of the scale divisions to be larger. 1. … 2. … [2] (iii) As a result of the changes in (ii), what other change is needed to enable the thermometer to be used for the same temperature range? … [1] (b) The expansion of a liquid is an example of a physical property that may be used to measure temperature. State two other physical properties that may also be used to measure temperature. 1. the … of … 2. the … of … [2] [Total: 6]

6 marks

Mark scheme: 1 (a) (i) (liquid) has a uniform expansion / expands at a constant rate / expands evenly / expands linearly B1 (ii) any two from: larger bulb / wider / longer bulb more liquid narrower capillary / tube use liquid with greater expansion B2 (iii) thermometer must be longer B1 (b) any 2 from: resistance / conductance of a metal / wire / conductor / thermistor voltage / current of a thermocouple volume / pressure / expansion / contraction of a gas colour of a metal amount of radiation OR frequency OR wavelength of radiation from a metal / furnace colour / arrangement of liquid crystals expansion of a solid / any dimension of a solid bending of a bimetallic strip B2 [Total: 6]

This question in 0625/31 May/June 2014

7 (a) The following are three statements about boiling. • A liquid boils at a fixed temperature. • During boiling, vapour can form at any point within the liquid. • Without a supply of thermal energy, boiling stops. Complete the following equivalent statements about evaporation. • A liquid evaporates at … … . • During evaporation … … . • Without a supply of thermal energy, evaporation … . [3] (b) A pan containing water boiling at 100 °C is standing on an electrically heated hot-plate. In 20 minutes, 0.075 kg of water is lost as steam. The specific latent heat of vaporisation of water is 2.25 × 106 J / kg. (i) Calculate the energy used in converting 0.075 kg of boiling water to steam. energy = … [2] (ii) The hot-plate operates at 240 V, 0.65 A. Calculate the energy supplied to the hot-plate in 20 minutes. energy = … [2] (iii) Suggest why the answers to (b)(i) and (b)(ii) are not the same. … … [1] [Total: 8]

8 marks

Mark scheme: 7 (a) (a liquid evaporates) at any temperature / below the boiling point / over a range of temperatures / below 100 oC / at different temperatures / not at a fixed temperature B1 (during evaporation) vapour forms at / escapes from the surface of the liquid B1 (without a supply of thermal energy,) evaporation continues / occurs / doesn’t stop OR causes liquid to cool / is slower / reduces B1 (b) (i) (Q =) mL C1 OR 0.075 × 2.25 × 106 1.7 × 105 J A1 (ii) (E =) VIt OR 240 × 0.65 × (20 × 60) C1 OR P = IV and P = E / t OR energy / time 1.9 × 105 J A1 (iii) energy is transferred to the surroundings OR in heating the surroundings / air / atmosphere / hot-plate B1 [Total: 8]

This question in 0625/31 May/June 2014

4 (a) Define the specific heat capacity of a substance. … … [2] (b) Fig. 4.1 shows a cylinder of aluminium heated by an electric heater. electric heater C.I.E. Power Pack thermometer V + – aluminium cylinder Fig. 4.1 The mass of the cylinder is 800 g. The heater delivers 8700 J of thermal energy to the cylinder and the temperature of the cylinder increases by 12 °C. (i) Calculate a value for the specific heat capacity of aluminium. specific heat capacity = … [2] (ii) Calculate the thermal capacity (heat capacity) of the aluminium cylinder. thermal capacity = … [2] (c) State and explain a method of improving the accuracy of the experiment. … … … [2] [Total: 8]

8 marks

Mark scheme: 4 (a) (thermal) energy / heat to heat unit mass / 1 kg / 1 g B1 by unit temperature / 1 °C / 1 K B1 (b) (i) SHC= Q / (m∆T) in any form or Q / (m∆T) words, symbols or numbers C1 (SHC = 8700 / 800 × 12=) 0.91 J / (g °C) or 910 J / (kg °C) A1 (ii) th. cap. = Q / ∆T in any form or Q / ∆T or m × SHC words, symbols or numbers C1 (th. cap. = 8700 / 12 or 0.906 × 800 or 906 × 0.8 =) 730 J / °C or 725 J / °C A1 (c) lag (cylinder) / wait after heating until temperature stable / at max. value M1 prevents / reduces heat losses or heat (energy) takes time to flow throughout block A1 throughout 4(c), reward correct alternative physics which answers the question e.g. use greater power to reduce expt time and hence energy lost ignore: repeats or use thermometer with low thermal capacity [Total: 8]

This question in 0625/32 May/June 2014

5 (a) In the box below, sketch a diagram to represent the molecular structure of a liquid. Show the molecules as small circles of equal size. [2] (b) A teacher in a school laboratory pours liquid ethanol from a bottle into a glass dish. The glass dish rests on an electronic balance. Although the temperature of the laboratory is below the boiling point of ethanol, the mass of ethanol in the dish quickly decreases as ethanol evaporates. (i) State the effect of this evaporation on the temperature of the remaining ethanol. … [1] (ii) Explain, in terms of the ethanol molecules, why this is happening. … … [1] (iii) The specific latent heat of vaporisation of ethanol is 850 J / g. Calculate the thermal energy required to evaporate 3.4 g of ethanol. thermal energy = … [2] (iv) Suggest two ways in which the rate of evaporation of ethanol from the dish can be reduced. 1. … 2. … [2] [Total: 8]

8 marks

Mark scheme: 5 (a) diagram shows (molecules) randomly positioned M1 diagram shows most (molecules) touching/very closely spaced A1 (b) (i) (temperature) decreases B1 (ii) more energetic/faster molecules escape from surface/overcome forces of attraction B1 (iii) E = ml in any form OR ml C1 2900 J A1 (iv) any two from: • cover/decrease surface area • reduce temperature • reduce draught owtte • increase humidity of air B2 [Total: 8]

This question in 0625/32 Oct/Nov 2014

6 A technician is designing a liquid-in-glass thermometer. The following is a list of properties of the thermometer that she is considering. sensitivity range speed of response linearity (a) (i) 1. Which one of these properties is affected by the length of the stem of the thermometer? … 2. Explain your answer. … … [2] (ii) 1. Which property is affected by the diameter of the capillary? … 2. Explain your answer. … … [2] (b) The thermometer is to be used to measure temperatures between −10 °C and 50 °C. The technician considers using water or red-coloured alcohol as the liquid in the thermometer. (i) Write down which liquid would be suitable. … (ii) Give two reasons for your answer. 1. … … 2. … … [2] [Total: 6]

6 marks

Mark scheme: 6 (a) (i) 1. range M1 2. correct link between stem length and range/top temperature/expansion A1 (ii) 1. sensitivity M1 2. correct link between capilliary diameter and sensitivity/movement of thread A1 (b) (i) (coloured) alcohol (note: no mark for this point, but must be present for subsequent marks to be awarded) M0 (ii) any two from: • water will freeze / alcohol doesn’t freeze • coloured alcohol (clearly) visible • alcohol has even expansion / water has uneven expansion • alcohol expands more / water expands less • alcohol has lower SHC/thermal capacity • alcohol does not stick to glass B2 [Total: 6] nd

This question in 0625/32 Oct/Nov 2014

5 (a) State what is meant by the specific heat capacity of a substance. … … … [2] (b) A student carries out an experiment to find the specific heat capacity of aluminium. He uses an electric heater and a thermometer, inserted into separate holes in an aluminium block. The following data are obtained. mass of aluminium block = 2.0 kg power of heating element = 420 W time of heating = 95 s initial temperature of block = 19.5 °C final temperature of block = 40.5 °C Calculate the value of the specific heat capacity of aluminium given by this experiment. specific heat capacity = … [4] (c) In the experiment in (b), no attempt is made to prevent loss of thermal energy from the surfaces of the block. Suggest two actions the student could take to reduce the loss of thermal energy from the surfaces of the block. 1. … 2. … [2] [Total: 8]

8 marks

Mark scheme: 5 (a) energy/heat required to increase temperature • of 1 kg / 1 g / unit mass (of the substance) B1 • by 1 °C / 1 K / unit temperature B1 (b) E = m c ∆θ in any form OR (c =) E ÷ m ∆θ C1 E = P t in any form OR 420 × 95 (= 39 900) C1 ∆θ = [40.5 – 19.5] OR 21 C1 (c = 39 900÷42 =) 950 J / (kg °C) A1 (c) any two separate points from: max. B2 • lagging / insulation (around block) OR insulate (the block) • raise temperature of block by a smaller amount OR heat for a shorter time OR use lower power heater for same time OR higher power for same temperature rise / shorter time • polish the surface of the block OR wrap the block in shiny material OR paint (shiny) white • reduce initial temperature of block (to below room temperature) OR raise temperature of room • reduce draughts [Total: 8]

This question in 0625/31 May/June 2015

4 A liquid-in-glass thermometer has a linear scale and a range of 120 °C. (a) State what is meant by a linear scale. … … [1] (b) The highest temperature that this thermometer can measure is 110 °C. State the lowest temperature that it can measure. lowest temperature = … [1] (c) A second liquid-in-glass thermometer has the same range but it has a greater sensitivity. Suggest two ways in which the second thermometer might differ from the first. 1. … 2. … [2] (d) A thermometer has a bulb that is painted white and is shiny. It is placed in boiling water for several minutes. It is then removed from the water and is held in air. Fig. 4.1 shows how the thermometer reading changes during the next 8 minutes. 100 temperature / °C 80 60 40 20 0 0 2 4 6 8 time / minutes Fig. 4.1 The bulb of this thermometer is now re-painted so that it has a matt, black surface. The procedure is repeated. (i) On Fig. 4.1, sketch a second line to suggest how the reading of the re-painted thermometer changes during the 8 minutes. [2] (ii) Tick one of the boxes to show how painting the bulb black affects the linearity of the scale, the range and the sensitivity of the thermometer. The linearity, the range and the sensitivity all change. Only the linearity and the range change. Only the linearity and the sensitivity change. Only the range and the sensitivity change. Only the linearity changes. Only the range changes. Only the sensitivity changes. None of these properties changes. [1] [Total: 7]

7 marks

Mark scheme: 4 (a) same distance moved (by thread) for same temperature change B1 (b) – 10 °C B1 (c) any two from: max. B2 • longer stem • bigger bulb OR more liquid • narrower bore OR thinner thread • liquid with greater expansivity (d) (i) falls from 100 °C with a decreasing gradient AND at a faster rate B1 finishes horizontal along 20 °C line B1 (ii) only bottom box ticked B1 [Total: 7]

This question in 0625/33 May/June 2015

5 (a) State what is meant by the specific latent heat of fusion (melting) of a substance. … … [2] (b) Ice cubes of total mass 70 g, and at 0 °C, are put into a drink of lemonade of mass 300 g. All the ice melts as 23 500 J of thermal energy transfers from the lemonade to the ice. The final temperature of the drink is 0 °C. (i) Calculate the specific latent heat of fusion for ice. specific latent heat of fusion = … [2] (ii) The thermal energy that causes the ice to melt is transferred from the lemonade as it cools. The loss of this thermal energy causes the temperature of the 300 g of the lemonade to fall by 19 °C. Calculate the specific heat capacity of the lemonade. specific heat capacity = … [2] (iii) The melting ice floats on top of the lemonade. Explain the process by which the lemonade at the bottom of the drink becomes cold. … … … [2] [Total: 8]

8 marks

Mark scheme: 5 (a) energy/heat needed to change state of substance/melt B1 (from solid to liquid at constant temperature / melting point) per kg / per unit mass B1 (b) (i) (lf=) Q ÷ m in any form: words, symbols, numbers C1 340 J / kg OR 336 J / g OR equivalent in J / kg A1 (ii) (c =) Q ÷ [m ∆T] in any form: words, symbols, numbers C1 4.1 J / (g °C) OR 4100 J / (kg °C) A1 (iii) cold water denser AND sinks B1 convection (current) OR circulation OR warmer water rises B1 [Total: 8]

This question in 0625/33 May/June 2015

5 (a) Smoke particles are introduced into a glass box containing air. Light shines into the box so that, when observed through a microscope, the smoke particles can be seen as bright points of light. Describe the motion of the smoke particles and account for this motion in terms of the air molecules. … … … … … … [4] (b) Fig. 5.1 shows a quantity of gas in a cylinder sealed by a piston that is free to move. gas cylinder piston Fig. 5.1 (i) The temperature of the gas is increased. State what happens, if anything, 1. to the piston, … 2. to the pressure of the gas. … [2] (ii) The piston is now fixed in place and the temperature of the gas is increased further. Explain, in terms of the behaviour of molecules, what happens to the pressure of the gas. … … … [2] [Total: 8]

8 marks

Mark scheme: 5 (a) any two of motion of smoke particles: random / haphazard / unpredictable movement; sudden changes of direction / zig-zag motion; appear / disappear from view OR go out of / come into focus; B2 any two of conclusions about air molecules: collide with smoke particles OR smoke particles collide with / moved by air molecules; air molecules fast(er); air molecules small(er) / light(er); move randomly; B2 (b) (i) 1 (the piston) moves to the right / out(wards) / is pushed away B1 2 (the pressure of the gas) remains constant B1 (ii) (pressure of the gas) increases B1 more frequent collisions (of gas molecules) with piston / walls / container OR (gas molecules) collide with piston / walls / container with great(er) force B1 [Total: 8]

This question in 0625/31 Oct/Nov 2015

5 (a) X and Y are liquid-in-glass thermometers. The scale of each thermometer starts at 0 °C. X has a large range, good linearity and high sensitivity. Y has a small range, poor linearity and low sensitivity. Explain what is meant by (i) the difference in their ranges, … … (ii) the difference in their linearities, … … (iii) the difference in their sensitivities. … … [3] (b) A thermocouple is used to measure the temperature of a small volume of liquid. (i) Draw and label a sketch of the arrangement. [3] (ii) The temperature of the liquid is changing rapidly. Explain why the thermocouple is able to respond quickly to this rapid change. … … … [2] [Total: 8]

8 marks

Mark scheme: 5 (a) in all parts accept by implication reference to X e.g. in (i) accept “it covers a greater range of temperature” (i) X covers greater range of temperature OR (goes to) higher temperature OR greater range expressed numerically B1 (ii) liquid in X expands uniformly (with temperature rise) B1 (iii) (for the same temperature rise,) the liquid in X expands more B1 (b) (i) two junctions correctly connected to each other and to meter OR one junction between wires and other junction at connection to meter M1 temperature difference between junctions A1 two wires correctly labelled as made of different materials, accept labels metal A & metal B NOT 3 different metals labelled B1 (ii) junction (in liquid) has low mass / small heat capacity / small size B1 temperature of junction reacts quickly / quickly reaches temperature of liquid / heat or cools faster B1 [Total: 8]

This question in 0625/32 Oct/Nov 2015

5 (a) State two examples of physical properties that vary with temperature and that may be used for the measurement of temperature. 1. … 2. … [2] (b) When first manufactured, a liquid-in-glass thermometer has no scale markings. (i) Describe the procedure needed to determine 1. the position on the thermometer of the lower fixed point, … … … 2. the position on the thermometer of the upper fixed point. … … … [3] (ii) Explain why 1. the graduations marked on the thermometer between the fixed points are spaced equally, … … [1] 2. the expansion of the glass of the thermometer is ignored. … … [1] [Total: 7]

7 marks

Mark scheme: 5 (a) any two from: volume (of a liquid / gas); resistance (of a metal); voltage (of a thermocouple); other appropriate examples; B2 (b) (i) 1 place bulb in ice and water mixture AND mark liquid level B1 2 place bulb in steam from boiling water AND mark liquid level B1 pure ice OR pure water mentioned in 1 OR at normal atmospheric pressure mentioned in 2 B1 (ii) 1 liquid expands uniformly (as temperature rises) OR capillary / tube has uniform diameter / cross-sectional (area) B1 2 glass expands much less than the liquid or (also) expands linearly B1 [Total: 7]

This question in 0625/33 Oct/Nov 2015

9 (a) Place one tick in each row of the table to indicate one use of a thermistor and one use of a transistor. magnetic heat light field rectifier switch detector detector detector thermistor transistor [2] (b) In Fig. 9.1, lamp A is not glowing brightly. B 6 V A Fig. 9.1 Suggest and explain what could be done to component B to make lamp A glow brightly. … … … … … … [4] [Total: 6]

6 marks

Mark scheme: 9 (a) tick for thermistor under: heat detector B1 tick for transistor under: switch B1 (b) increase light intensity / brightness / illuminate B B1 resistance (of B) decreases cao B1 voltage at mid-point increases OR greater (share of) voltage M1 (more) current flows (through lamp) A1 [Total: 6]

This question in 0625/33 Oct/Nov 2015

7 Fig. 7.1 shows equipment used to demonstrate thermal expansion. pointer copper rod roller fixed block support heat Fig. 7.1 (a) The copper rod is heated and expands. It turns the roller and moves the pointer. On Fig. 7.1, draw the new position of the pointer. [1] (b) As the rod is heated, some of its properties change. Identify how each property changes. Place one tick in each row of the table. stays the property of rod decreases increases same volume mass density [3] (c) Suggest one disadvantage of thermal expansion. … [1] [Total: 5]

5 marks

Mark scheme: 7(a) to the left OR anticlockwise B1 7(b) row 1 – increases B1 row 2 – stays the same B1 row 3 – decreases B1 7(c) electric cables lower to ground OR telephone lines in summer OR buckling tracks B1 Total: 5

This question in 0625/31 May/June 2016

4 A student is investigating a mixture of water and ice. The water and ice are at the same temperature. He uses a thermometer. (a) Fig. 4.1 shows a thermometer. X Y narrow tube –10 0 10 20 30 40 50 60 70 80 90 100 110 °C scale glass Fig. 4.1 (i) On Fig. 4.1, label X and Y. [2] (ii) The thermometer is put into the mixture of water and ice. On Fig. 4.2, draw an arrow pointing to the reading on the scale. [1] –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 4.2 (b) The beaker of ice and water is left in a warm room for five hours. State what happens to the ice during this time. Describe this process in terms of the molecules in the ice. … … … … … … [4] [Total: 7]

7 marks

Mark scheme: 4(a)(i) X: bulb Y: liquid (thread) B1 B1 4(a)(ii) arrow at 0 °C B1 4(b) ice melts any three from: molecules gain energy (from surroundings) molecules vibrate faster break bonds between molecules molecules move freely B1 B3 Total: 7

This question in 0625/32 May/June 2016

8 Researchers have found that the best temperature for drinking coffee is 60 °C. A designer has developed a new type of cup for keeping coffee at 60 °C. The cup is shown in Fig. 8.1. plastic lid inner steel walls coffee shiny outer steel wall material Z vacuum Fig. 8.1 Material Z has a melting point of 60 °C. At room temperature, material Z is solid. Coffee, at a temperature of 90 °C, is poured into the cup. The coffee cools rapidly to 60 °C. (a) State what happens to material Z when the hot coffee is poured into the cup. … [1] (b) Explain how the features of the cup enable the coffee to be kept at 60 °C for a long time. plastic lid … … … vacuum … … … shiny outer steel wall … … … material Z … … … … … [5] [Total: 6]

6 marks

Mark scheme: 8(a) (material Z) melts B1 8(b) any five from: (plastic lid) is a good insulator (plastic lid) reduces ( heat loss by) convection (plastic lid) reduces ( heat loss by) evaporation (vacuum) reduces / prevents (heat loss by) convection (vacuum) reduces / prevents (heat loss by) conduction shiny / silver surface is a poor radiator / bad emitter (of thermal energy) at 60 °C material Z solidifies material Z maintains a constant temperature (60 °C) during solidification / internal energy is given out B5 Total: 6

This question in 0625/32 May/June 2016

4 A student is investigating a mixture of water and ice. The water and ice are at the same temperature. He uses a thermometer. (a) Fig. 4.1 shows a thermometer. X Y narrow tube –10 0 10 20 30 40 50 60 70 80 90 100 110 °C scale glass Fig. 4.1 (i) On Fig. 4.1, label X and Y. [2] (ii) The thermometer is put into the mixture of water and ice. On Fig. 4.2, draw an arrow pointing to the reading on the scale. [1] –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 4.2 (b) The beaker of ice and water is left in a warm room for five hours. State what happens to the ice during this time. Describe this process in terms of the molecules in the ice. … … … … … … [4] [Total: 7]

7 marks

Mark scheme: 4(a)(i) X: bulb Y: liquid (thread) B1 B1 4(a)(ii) arrow at 0 °C B1 4(b) ice melts any three from: molecules gain energy (from surroundings) molecules vibrate faster break bonds between molecules molecules move freely B1 B3 Total: 7

This question in 0625/33 May/June 2016

8 Researchers have found that the best temperature for drinking coffee is 60 °C. A designer has developed a new type of cup for keeping coffee at 60 °C. The cup is shown in Fig. 8.1. plastic lid inner steel walls coffee shiny outer steel wall material Z vacuum Fig. 8.1 Material Z has a melting point of 60 °C. At room temperature, material Z is solid. Coffee, at a temperature of 90 °C, is poured into the cup. The coffee cools rapidly to 60 °C. (a) State what happens to material Z when the hot coffee is poured into the cup. … [1] (b) Explain how the features of the cup enable the coffee to be kept at 60 °C for a long time. plastic lid … … … vacuum … … … shiny outer steel wall … … … material Z … … … … … [5] [Total: 6]

6 marks

Mark scheme: 8(a) (material Z) melts B1 8(b) any five from: (plastic lid) is a good insulator (plastic lid) reduces ( heat loss by) convection (plastic lid) reduces ( heat loss by) evaporation (vacuum) reduces / prevents (heat loss by) convection (vacuum) reduces / prevents (heat loss by) conduction shiny / silver surface is a poor radiator / bad emitter (of thermal energy) at 60 °C material Z solidifies material Z maintains a constant temperature (60 °C) during solidification / internal energy is given out B5 Total: 6

This question in 0625/33 May/June 2016

6 Water can exist as ice, liquid water and steam. Fig. 6.1 represents the arrangement of the molecules in the three forms of water. ice liquid water steam Fig. 6.1 (a) Each diagram in Fig. 6.2 shows a change of state. Add the correct label for each change. The first has been done for you. condensation … … … [3] Fig. 6.2 (b) Some gas is heated at constant pressure. Describe what happens to the molecules of gas as the temperature increases. … … [2] (c) Fig. 6.3 shows a metal bar. height width length Fig. 6.3 When the metal bar is heated, the bar expands. Identify the dimensions that increase in size when the bar is heated. Tick (3) all boxes that apply. length width height [1] (d) State one use and one disadvantage of the expansion of materials when they are heated. use … disadvantage … [2] [Total: 8]

8 marks

Mark scheme: 6(a) evaporation / boiling solidification / freezing melting B3 6(b) faster movement / gain kinetic energy B1 larger separation of molecules owtte B1 6(c) all boxes ticked B1 6(d) bimetal strips B1 train rails buckling B1 Total: 8

This question in 0625/32 Feb/March 2017

6 Fig. 6.1 shows a liquid-in-glass thermometer. liquid °C –10 0 10 20 30 40 50 60 70 80 90 100 110 Fig. 6.1 (a) (i) Which of these metals is often used for the liquid in thermometers? Tick the correct box. magnesium mercury silver [1] (ii) The thermometer is placed inside a freezer containing ice. Suggest the temperature of the ice. Draw an arrow on Fig. 6.1. [1] (iii) A thermometer is calibrated using two fixed points. State the temperatures of the two fixed points. lower fixed point = … °C upper fixed point = … °C [1] (b) The sentences are about thermal processes. Complete each sentence. Use words from the box. Each word may be used once, more than once or not at all. conductor convection emitter insulator radiation reflection • A dull black surface is a good … • Copper is used to make pans because it is a good thermal … • In fluids, thermal energy is transferred mainly by … • Thermal energy reaches Earth from the Sun by means of … [4] [Total: 7]

7 marks

Mark scheme: 6(a)(i) mercury B1 6(a)(ii) arrow between 0 o C and start of capillary tube B1 6(a)(iii) 0 (oC) AND 100 (o C) B1 6(b) emitter B1 conductor B1 convection B1 radiation B1

This question in 0625/33 Oct/Nov 2017

6 A student constructs a device for absorbing thermal energy from the Sun. Fig. 6.1 shows the device. Sun thermometer Tank A thermometer cold water white plastic pipe Tank B warm water Fig. 6.1 The student places the white plastic pipe in sunlight. The cold water flows slowly from Tank A to Tank B. Energy from the Sun heats the water in the pipe. Fig. 6.2 shows the temperatures in Tank A and Tank B. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Thermometer showing temperature in Tank A. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Thermometer showing temperature in Tank B. Fig. 6.2 (a) Determine the rise in temperature of the water. temperature rise = … ° C [1] (b) The student wants to increase the thermal energy absorbed by the water in the pipe. Suggest three improvements he can make to increase the thermal energy absorbed. 1 … … 2 … … 3 … … [3] (c) Describe how the thermal energy is transferred from the Sun to the water inside the pipe. … … [2] [Total: 6]

6 marks

Mark scheme: 6(a) (26 – 23 =) 3(°C) 1 6(b) any three from: use metal pipe paint black or use black pipe use matt or dull (paint) (place) reflector behind pipe use long(er) pipe use pipe with great(er) surface area slow(er) flow rate (place) glass/(clear) plastic cover over pipe 3 6(c) infra-red (radiation through space/air) 1 conduction through pipe 1

This question in 0625/31 May/June 2018

4 A Bunsen burner heats a beaker of water, as shown in Fig. 4.1. thermometer stand beaker water Bunsen burner Fig. 4.1 (a) (i) Fig. 4.2 shows the thermometer used in Fig. 4.1. State the temperature shown on the thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 4.2 temperature = … ° C [1] (ii) The thermometer shown in Fig. 4.2 uses a physical property that changes with temperature. Indicate the measurable property that changes with temperature. Tick one box. expansion of glass expansion of liquid colour of liquid colour of glass [1] (b) Thermal energy (heat) transfers through the bottom of the beaker to the water. State the name given to this process. … [1] (c) Thermal energy transfers throughout the water in the beaker. Describe and explain how this happens. … … … … … [4] [Total: 7]

7 marks

Mark scheme: 4(a)(i) 38 (°C) 1 4(a)(ii) 2nd box ticked i.e. expansion of liquid 1 4(b) conduction 1 4(c) any three from: water is a fluid water molecules gain (kinetic) energy/move faster/further apart water expands/volume increases warm/hot water or molecules rises convection (current created) cooler/cold/water falls/sinks (to be heated again) 3 correct reference to density change of water 1

This question in 0625/32 May/June 2018

5 (a) State the meaning of the term thermal capacity. … … [1] (b) When a material is cooled or heated there may be a change of state. Complete each statement by using words from the box. Each word can be used once, more than once or not at all. condensation evaporation freezing melting The change from solid to liquid is called … The change from liquid to gas is called … The change from liquid to solid is called … The change from gas to liquid is called … . [4] (c) A student heats a gas and keeps its volume constant. State and explain the effect on the pressure of the gas. In your answer, use your ideas about molecules. … … … … [3] [Total: 8]

8 marks

Mark scheme: 5(a) B1 5(b) melting evaporation or boiling freezing condensation or condensing B4 5(c) increased pressure B1 more collisions or hit walls of container harder or more often B1 molecules move faster OR have more (kinetic) energy B1

This question in 0625/32 Oct/Nov 2018

6 A liquid-in-glass thermometer is placed in some ice made from pure water. The ice is heated. It changes to water and then to steam. The graph in Fig. 6.1 shows how the temperature varies with time. The values of temperature are missing from the y-axis. temperature / °C Y X 0 10 20 30 40 50 60 70 time / minutes Fig. 6.1 (a) On Fig. 6.1, suggest a value for the temperature at each of the three points marked on the y-axis. Write a value in each of the boxes. [2] (b) In both section X and section Y the line on the graph is horizontal. For each section, state the name for the process taking place and explain what is happening to the molecules. (i) section X name … explanation … … … … [2] (ii) section Y name … explanation … … … … [2] [Total: 6]

6 marks

Mark scheme: 6(a) 0 AND 100 correctly labelled M1 36 A1 6(b)(i) Melting B1 Any one of: molecules gain energy molecule (begin to) break (some) bonds arrangement becomes irregular or arrangement changes B1 6(b)(ii) boiling B1 Any one of: molecules break (all) bonds molecules move (more) freely molecules become widely separated or far apart B1

This question in 0625/31 May/June 2019

6 (a) Fig. 6.1 shows a liquid-in-glass thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 6.1 (i) State the name of a liquid used in liquid-in-glass thermometers. … [1] (ii) The thermometer is calibrated using two fixed points. State the values of these fixed points. … °C and … °C [1] (b) A student heats some water in a metal can, as shown in Fig. 6.2. water movement metal can of water heat Fig. 6.2 (i) Complete the sentence. Choose a word from the box. conduction convection radiation Thermal (heat) energy moves through the metal can by … [1] (ii) Describe how thermal energy is transferred throughout the water. Include your ideas about density changes. … … … … … … … [3] [Total: 6]

6 marks

Mark scheme: 6(a)(i) mercury or alcohol B1 6(a)(ii) 0 (°C) AND 100 (°C) B1 6(b)(i) conduction B1 6(b)(ii) Any three from: (heat causes) water molecules (to) move further apart OR (hot) water expands / volume increases (hot water) is less dense NOT molecules less dense/expand (so hot / less dense) water rises (and is replaced by cooler / more dense water) convection / current (in water) B3

This question in 0625/32 Oct/Nov 2019

7 (a) Complete the sentences. Add the missing word to each of the blank spaces. The unit of temperature is called the … . The physical property that varies with temperature in a liquid-in-glass thermometer is the … of the liquid. [2] (b) A student has a thermometer without a marked scale. To produce a scale for the thermometer, the student must use two fixed points. Give the temperature value for each fixed point and describe what happens to water at each of these temperatures. Lower fixed point … … Upper fixed point … … [4] [Total: 6]

6 marks

Mark scheme: 7(a) (degrees) celsius OR oC volume B1 B1 7(b) Lower 0 oC (water) freezes OR turns to ice Upper 100 oC (water) boils B1 B1 B1 B1

This question in 0625/33 Oct/Nov 2019

7 (a) Equal volumes of steel, oil and hydrogen are heated from 20 °C to 60 °C. Their volumes increase by thermal expansion. State which of these substances has the greatest increase in volume. … [1] (b) Fig. 7.1 shows a liquid-in-glass thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 7.1 (i) State the temperature reading on the thermometer. … [1] (ii) State the temperature range of the thermometer. … [1] (iii) State the values of the fixed points of the Celsius scale of temperature. … [1] (c) The liquid-in-glass thermometer uses the thermal expansion of mercury. State and explain one other application or consequence of thermal expansion. … … … … … [3] [Total: 7]

7 marks

Mark scheme: 7(a) hydrogen (gas) B1 7(b)(i) 27 (°C) B1 7(b)(ii) –10 (°C) to 110 (°C) B1 7(b)(iii) 0 (°C) AND 100 (°C) B1 7(c) use / consequence of thermal expansion identified B1 description of effect B1 explanation of effect B1

This question in 0625/32 Feb/March 2020

6 Fig. 6.1 shows a liquid-in-glass thermometer. liquid –10 0 10 20 30 40 50 60 70 80 90 100 110 ice point liquid Fig. 6.1 (a) (i) This thermometer is used for measuring temperatures in science experiments. State the unit for measuring temperature. … [1] (ii) On Fig. 6.1, an arrow points to the temperature reading when the thermometer is placed in pure melting ice. This is labelled ice point. On Fig. 6.1, draw an arrow pointing to the temperature reading when the thermometer is at the upper fixed point. Label this arrow steam point. [1] (b) A liquid-in-glass thermometer uses the property of expansion of a liquid to measure temperature. State one other application or consequence of thermal expansion. … … [1] (c) A student is testing how different surfaces absorb radiant heat. The student puts two metal plates in holders and places them on either side of a radiant heater as shown in Fig. 6.2. One plate has a shiny metal side facing towards the heater and the other plate has a dull black side facing towards the heater. A metal disc is attached to each plate using wax. shiny metal radiant dull black surface heater surface metal disc metal disc wax wax 8 cm 10 cm Fig. 6.2 (i) The student turns on the radiant heater and starts a stop-clock. The wax on the plate with a dull black side melts and the metal disc falls off the plate 53 seconds after the stop-clock is started. The metal disc on the plate with a shiny metal side remains attached for another 32 seconds after the metal disc on the first plate falls. Explain why the metal disc on the plate with a dull black side falls before the metal disc on the plate with a shiny metal side. … … … … … [2] (ii) Another student observes the experiment shown in Fig. 6.2 and says that the comparison of the two plates is not fair. Suggest why the experiment is not fair. … … [2] [Total: 7]

7 marks

Mark scheme: 6(a)(i) °C or degrees celcius B1 6(a)(ii) arrow at 100 (labelled steam) B1 6(b) use OR consequence of thermal expansion identified B1 6(c)(i) black is better / best absorber B1 (so) temperature of wax rises faster on black plate B1 6(c)(ii) (for a valid comparison all independent) variables must be the same B1 plates / discs should be equal distances (from heater) (owtte) B1

This question in 0625/31 May/June 2020

4 (a) Match each description with the correct state of matter in Table 4.1. Write the correct letter in Table 4.1. A – Molecules move around freely and are far apart from each other. B – Molecules vibrate about fixed positions. C – Molecules move around randomly and are close to each other. Table 4.1 state of matter description solids liquids gases [2] (b) Some students heat water in a beaker. They measure the temperature every minute. They heat the water for 8 minutes until it boils, and then continue to heat it for a further 5 minutes. Describe and explain how the temperature of the water changes during the 13 minutes. … … … … … … … [3] [Total: 5]

5 marks

Mark scheme: 4(a) B C A B2 4(b) any three from: during first eight minutes temp rises (because) internal energy of water rises (from thermal energy input) during next five minutes temperature is constant / stays the same (because) internal energy does not rise (at boiling point) B3

This question in 0625/32 May/June 2020

6 (a) Fig. 6.1 represents three changes of state. Each pair of diagrams A, B and C shows the arrangement of molecules in a substance before and after it changes state. before after A B C Fig. 6.1 Give the term used for each change of state. A … B … C … [3] (b) A student attaches a liquid-in-glass thermometer to a ruler. The thermometer does not have a marked scale. Fig. 6.2 shows the arrangement. ruler cm 15 14 thermometer 13 12 11 10 9 8 mercury level 7 6 5 4 3 2 1 0 Fig. 6.2 The student places the thermometer in steam. The mercury rises to 11 cm on the ruler. The student places the thermometer in melting ice. The mercury decreases to 1 cm on the ruler. Determine the temperature indicated by the mercury level in Fig. 6.2. temperature = … °C [3] [Total: 6]

6 marks

Mark scheme: 6(a) A: melting B1 B: evaporating / boiling / vapourising B1 C: freezing / solidifying B1 6(b) 1(.0) cm = 10 °C OR (6(.0) – 1(.0)) = 5 B1 × − 5 100 11 1 C1 (temperature =) 50 (°C) A1

This question in 0625/31 Oct/Nov 2020

5 A beaker contains water. Some of the water evaporates. (a) Describe and explain how the water evaporates. Use your ideas about molecules. … … … [2] (b) Evaporation changes the temperature of the water that remains in the beaker. State and explain the change in temperature of the water due to evaporation. … … … [3] [Total: 5]

5 marks

Mark scheme: 5(a) high(er / est) energy molecules B1 (near the surface) escape (from surface) B1 5(b) (temperature) decreases B1 AND any two from: higher energy molecules have escaped (leaving) lower energy particles behind (so) average energy of remaining molecules is lower B2

This question in 0625/32 Oct/Nov 2020

5 (a) Fig. 5.1 shows diagrams of the arrangement of molecules in three states of matter and shows descriptions of how the molecules move. arrangement of molecules state of matter movement of molecules solid do not move move around while in contact with other molecules liquid move around freely vibrate about gas fixed positions Fig. 5.1 On Fig. 5.1, draw a line: • from each arrangement of molecules to the correct state of matter • from the state of matter to the correct description of the movement of molecules. [4] (b) A bicycle tyre contains air. The tyre is sealed and does not leak. The temperature of the air in the tyre increases by 20 °C. The volume of the tyre does not change. (i) State how the increase in temperature affects the motion of the air molecules in the tyre. … [1] (ii) State how the increase in temperature changes the pressure of the air in the tyre. … [1] (c) Fig. 5.2 shows a liquid-in-glass thermometer. … … narrow tube liquid Fig. 5.2 (i) Add the missing labels to Fig. 5.2. [2] (ii) The thermometer in Fig. 5.2 is designed to measure a range of temperatures from 0 °C to 100 °C. State the name of a suitable liquid for use in this thermometer. … [1] (iii) Describe and explain the changes in the thermometer in Fig. 5.2 when the temperature of the liquid increases. … … … [2] [Total: 11]

11 marks

Mark scheme: 5(a) arrangement: solid to 2nd box liquid to 3rd box 3 correct – 2 marks: 2 or 1 correct – 1 mark gas to 1st box movement: solid to 4th box liquid to 2nd box 3 correct – 2 marks: 2 or 1 correct – 1 mark gas to 3rd box B2 5(b)(i) move faster / speed up / more (kinetic) energy or wtte B1 5(b)(ii) (pressure) increases B1 5(c)(i) (temperature) scale B1 bulb OR reservoir B1 5(c)(ii) mercury B1 5(c)(iii) (liquid / mercury / alcohol) expands B1 liquid level / meniscus moves along tube / scale B1

This question in 0625/33 Oct/Nov 2020

6 (a) Fig. 6.1 shows a liquid-in-glass thermometer. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C bulb made from thin glass narrow tube Fig. 6.1 (i) State the temperature indicated on the thermometer in Fig. 6.1. … [1] (ii) Explain why: 1. the bulb is made from thin glass … … … [1] 2. the tube, along which the liquid expands, is narrow. … … … [1] (b) A substance cools from 40 °C to –20 °C. The substance takes 40 minutes to cool from 40 °C to its melting point of –12 °C. The substance then takes 20 minutes to freeze. On Fig. 6.2, sketch a temperature–time graph as the substance cools from 40 °C to –20 °C. 60 temperature / °C 40 20 0 0 10 20 30 40 50 60 70 80 time / minutes –20 – 40 Fig. 6.2 [4] [Total: 7]

7 marks

Mark scheme: 6(a)(i) 6(a)(ii)1 to enable rapid transfer of thermal energy to liquid in bulb B1 6(a)(ii)2 idea: (small change in volume OR temperature) produces large movement of mercury along capillary owtte B1 Question Answer Marks 6(b) any four from: • line starting at 40 °C • line showing decreasing temp with time for 40 minutes • line becoming horizontal at –12 °C • horizontal line for about 20 mins (by eye) • line showing decreasing temp after horizontal section B4

This question in 0625/32 May/June 2021

4 (a) A substance cools from 50 °C to 5.0 °C. Its melting point is 20 °C. The substance takes 30 minutes to cool from 50 °C to its melting point. The substance takes a total time of 80 minutes to cool from 50 °C to 5.0 °C. On Fig. 4.1, sketch a graph that shows how the temperature of the substance varies with time as it cools from 50 °C to 5.0 °C. 60 temperature / °C 40 20 0 0 10 20 30 40 50 60 70 80 time / min Fig. 4.1 [4] (b) Describe the arrangement and motion of the molecules in the substance when they are in the solid state. … … … … [2] [Total: 6]

6 marks

Mark scheme: 4(a) horizontal section at 20 °C B1 line starting at (0, 50) line decreasing (steadily) (from (0, 50)) to 20 °C in 30 minutes (by eye) line decreasing from 20 °C AND line reaches 5 °C at time of 80 mins B3 4(b) any two from: (in solid state molecules / they are) close(r)(than in liquids / gases) (in solid state molecules / they are) in regular arrangement (in solid state molecules / they are) in fixed positions (in solid state molecules / they can only) vibrate B2

This question in 0625/31 Oct/Nov 2021

7 (a) Fig. 7.1 shows a candle underneath a thin, metal fan. support for fan direction of rotation thin, metal fan candle Fig. 7.1 When the candle starts to burn, the fan starts to rotate around its support. Explain what causes the fan to rotate. … … … [3] (b) Fig. 7.2 shows a bimetallic strip. It is made of two metals, steel and copper, fastened together. The bimetallic strip is straight when the temperature is 25 °C. clamp steel temperature = 25 °C copper Fig. 7.2 Fig. 7.3 shows the bimetallic strip when the temperature is 40 °C. clamp steel temperature = 40 °C copper Fig. 7.3 (i) Draw the bimetallic strip when the temperature is 10 °C. [1] (ii) The bimetallic strip is used in a circuit, as shown in Fig. 7.4. The circuit is in a room. cell electric bell room temperature = 25 °C steel contacts copper Fig. 7.4 The room temperature is 25 °C. State and explain any changes in the circuit as the temperature of the room rises above 40 °C. … … [2] [Total: 6]

6 marks

Mark scheme: 7(a) any three from: convection (currents) (candle) heats air (warm) air less dense (warm) air rises (rising / moving) air pushes on fan B3 7(b)(i) strip curved downwards B1 7(b)(ii) bimetallic strip curves upwards B1 bell rings OR switches circuit on owtte B1

This question in 0625/32 Oct/Nov 2021

4 (a) State and explain one application of thermal expansion. You may draw a diagram to support your answer. … … … … [2] (b) Fig. 4.1 shows a flask with air trapped inside it. tight-fitting stopper flask air Fig. 4.1 Initially, the flask and air are at room temperature. The flask is then cooled in a refrigerator. (i) State the change in the pressure of the air in the flask as the air cools. … [1] (ii) Explain your answer to (b)(i). Use your ideas about air molecules. … … … … [3] [Total: 6]

6 marks

Mark scheme: 4(a) situation B1 explanation B1 4(b)(i) decreases B1 4(b)(ii) molecules slow(er)/less (kinetic) energy B1 hit (wall/flask) less often B1 hit (wall/flask) with less force B1

This question in 0625/33 May/June 2022

5 An engineer makes a device that absorbs thermal energy from the Sun. The absorbed energy heats water. In the device, cold water flows slowly from an upper tank, through a white plastic pipe, to a lower tank. Energy from the Sun heats the water as it flows, as shown in Fig. 5.1. upper cold water tank Sun white plastic pipe lower tank warm water Fig. 5.1 (a) The engineer measures the temperature of the water in each tank. State the name of the instrument used for measuring temperature. … [1] (b) (i) State the name of the process that transfers thermal energy from the Sun to the white plastic pipe. … [1] (ii) State the name of the process that transfers thermal energy through the plastic wall of the pipe to the water inside the pipe. … [1] (c) The engineer wants to increase the thermal energy absorbed by the water in the pipe. Suggest two improvements he can make to increase the thermal energy absorbed. In each case, explain why the suggestion increases the thermal energy absorbed. improvement 1 … … explanation … … improvement 2 … … explanation … … [4] [Total: 7]

7 marks

Mark scheme: 5(a) thermometer B1 5(b)(i) radiation B1 5(b)(ii) conduction B1 5(c) (dull) black pipes B1 better absorber (of radiation)/less reflection from pipes B1 foil/shiny metal behind pipes B1 reflects (radiation back to pipes) owtte B1 valid alternatives (B1)

This question in 0625/33 May/June 2022

3 (a) A liquid-in-glass thermometer has a scale with marks from –10 °C to 110 °C. A student checks the accuracy of the thermometer. Describe how to check the accuracy of: (i) the 100 °C mark on the thermometer scale … … [1] (ii) the 0 °C mark on the thermometer scale. … … [1] (iii) State the importance of the 0 °C and 100 °C marks on a thermometer scale. … [1] (b) We can measure temperature by using physical properties that vary with temperature. (i) State the physical property that we use to measure temperature in a liquid-in-glass thermometer. … [1] (ii) State another physical property that we use to measure temperature. … [1] [Total: 5]

5 marks

Mark scheme: 3(a)(i) steam above pure boiling water (at standard atmospheric pressure) B1 3(a)(ii) melting ice (made from pure water) B1 3(a)(iii) calibration owtte / scale / idea of increased accuracy B1 3(b)(i) expansion / contraction B1 3(b)(ii) length / resistance / e.m.f B1

This question in 0625/32 Oct/Nov 2022

4 A student has a block of solid metal at room temperature. (a) (i) Describe the arrangement, separation and motion of the particles in the solid metal. … … … … [3] (ii) The student cools the block of metal in a freezer. State the effect, if any, of cooling on the kinetic energy of the particles in the block of metal. … [1] (b) (i) State the name of the temperature at which particles have the least kinetic energy. … [1] (ii) State the value of temperature at which particles have the least kinetic energy. Include the unit. … [1] (c) The metal block emits thermal radiation from its surface. State two features of a surface that is a good emitter of thermal radiation. 1 … 2 … [2] [Total: 8]

8 marks

Mark scheme: 4(a)(i) any three from:  (particles are) fixed in position / place  regular arrangement  vibrating  close(r than in liquids or gases) B3 4(a)(ii) (kinetic energy) decreases B1 4(b)(i) absolute zero B1 4(b)(ii) –273 °C OR 0 K OR zero K / kelvin B1 4(c) black OR dark (colour) B1 dull OR rough (surface) B1

This question in 0625/32 May/June 2023

4 A tight-fitting lid keeps air inside a metal can. An airtight rubber bung holds a liquid-in-glass thermometer that is inserted through a hole in the lid, as shown in Fig. 4.1. liquid-in-glass thermometer lid metal can air Fig. 4.1 (a) (i) State what happens to the liquid in the thermometer when the air temperature rises. … [1] (ii) The temperature of the air in the can is 18 °C. Calculate the temperature of the air in kelvin. temperature = … K [2] (b) The can is placed in a refrigerator. The temperature of the air inside the can decreases. State and explain what happens to the pressure exerted by the air in the can. Use your ideas about gas particles. … … … … [3] (c) The air in another can exerts a pressure of 102 000 N / m2 on the lid. The area of the can lid is 0.0082 m2. Calculate the force on the lid due to the air in the can. force = … N [3] [Total: 9]

9 marks

Mark scheme: 4(a)(i) (liquid / it) expands B1 4(a)(ii) 273 + 18 C1 291 (K) A1 4(b) pressure decreases B1 any two from:  particles slower / less kinetic energy  collisions (with wall) less frequent  collide (with wall) with less force B2 4(c) (F =) P  A in any form C1 102 000  0.0082 C1 840 (N) A1

This question in 0625/33 May/June 2023

5 Fig. 5.1 shows a metal block at room temperature on a table. metal block table Fig. 5.1 (a) Describe the arrangement, separation and motion of the particles in the metal block. … … … … [3] (b) (i) The temperature of the metal block decreases. Describe any changes in the motion and separation of the particles in the metal block. … … [2] (ii) A scientist cools the metal block until its temperature is close to absolute zero. Describe the motion of the particles in the metal block. … … [1] (c) The weight of the metal block is 26 N. The area of the metal block in contact with the table is 42 cm2. Calculate the pressure on the table due to the metal block. pressure = … N / cm2 [3] [Total: 9]

9 marks

Mark scheme: 5(a) (particles are) fixed in position / in lattice OR regular / fixed arrangement / pattern B1 can only vibrate / no translational KE B1 close / closer (than in liquids or gases) B1 5(b)(i) (particles move) closer (as temperature decreases) B1 particles vibrate slower / less OR have smaller vibrations B1 5(b)(ii) (at absolute zero particles have) least / smallest vibrations B1 5(c) (P =) 0.62 (N / cm2) A3 (P =) 26 ÷ 42 (C2) (P =) F ÷ A (C1)

This question in 0625/32 May/June 2024

5 A sealed glass bottle contains air. The temperature of the air is 21 °C. (a) Calculate the temperature of the air in kelvin. temperature = … K [2] (b) The temperature of the air in the bottle decreases to 14 °C. State and explain what happens to the pressure inside the bottle. Use your ideas about gas particles. … … … … … … [4] [Total: 6]

6 marks

Mark scheme: 5(a) 294 (K) A2 273 (+ 21) (C1) 5(b) • low(er) pressure B1 any three from: • slow(er)particles or particles have less Kinetic Energy OR less energy in the kinetic store • less frequent collisions (with inside of bottle) B3 • (collide with) less force • pressure = force / area OR p = F  A

This question in 0625/32 Oct/Nov 2024

5 (a) Table 5.1 defines three specific temperatures. (i) Complete Table 5.1 by writing the correct temperature for each definition. Table 5.1 definition temperature / °C pure water boiling at standard atmospheric pressure pure ice melting at standard atmospheric pressure the lowest possible temperature of matter [3] (ii) The temperature of air in a room is 15 °C. Calculate the temperature of the air in kelvin. temperature = … K [2] (b) A teacher demonstrates thermal energy transfer through some metal rods. Fig. 5.1 shows the arrangement. metal rods Bunsen burner block of wood pins held on by wax Fig. 5.1 The metal rods are placed on a block of wood. The demonstration compares how quickly thermal energy is transferred to the wax at the end of each rod. (i) State the name of the process for thermal energy transfer through the metal rods. … [1] (ii) The rods are made from different metals. The rods have the same length and diameter. The ends of the rods in the Bunsen flame are at the same temperature. State how the demonstration shows which metal transfers thermal energy at the greatest rate. … … [2] (c) A playground includes a concrete area with white and black squares, as shown in Fig. 5.2. Fig. 5.2 The Sun shines on the concrete area during the day. The temperature of the concrete area increases. During the afternoon, students compare the temperature of the white squares with the temperature of the black squares. State and explain whether the white squares or the black squares have the higher temperature. Include the name of the process of thermal energy transfer from the Sun to the squares. … … … [2] [Total: 10]

10 marks

Mark scheme: 5(a)(i) B1 pure water boiling at standard atmospheric pressure 100 B1 pure ice melting at standard atmospheric pressure 0 the lowest possible temperature of matter –273 B1 5(a)(ii) 288 (K) A2 273 + 15 (C1) 5(b)(i) conduction B1 5(b)(ii) first wax to melt or first pin to fall off or the faster the pin falls off M1 the better the conductor / energy transfer / has the greatest rate A1 5(c) black (square) B1 AND either black – best/good absorber OR worse / poor reflector OR B1 white – best/good reflector OR worse / poor absorber of radiation / infrared (radiation)

This question in 0625/33 Oct/Nov 2024

6 A student warms some water in a metal container using an electric heater, as shown in Fig. 6.1. water metal container electric heater (hotplate) Fig. 6.1 (a) Describe the arrangement, separation and motion of the particles in liquid water. … … … … [3] (b) State how thermal energy moves through the metal container from the heater to the water. … [1] (c) Describe how thermal energy spreads throughout the water. … … … … [3] (d) The water is heated until it is boiling. The air pressure in the room is standard atmospheric pressure. State the temperature at which the water boils. temperature = … °C [1] [Total: 8]

8 marks

Mark scheme: 6(a) any three from (particles are:) B3 in a random arrangement close together OR slightly further apart than in solids move freely OR slide over each other collide (with each other) moving randomly 6(b) conduction B1 6(c) any three from: B3 convection idea that water at bottom of pan is warmed / temp of water at bottom increases warm water is less dense less dense / warm water rises OR more dense/colder water sinks 6(d) 100 (°C) B1

This question in 0625/32 Feb/March 2025

4 (a) Complete the sentences about the kinetic particle model of matter. (i) The movement of the particles in a gas is … … . [1] (ii) The forces between the particles in a gas are … … . [1] (iii) The gas exerts a pressure because the moving gas particles … … . [1] (iv) As the temperature of a fixed volume of gas decreases, the pressure exerted by the gas … . [1] (b) (i) State the value, in degrees Celsius, of the lowest possible temperature. lowest possible temperature = … °C [1] (ii) State the term used for the lowest possible temperature. … [1] [Total: 6]

6 marks

Mark scheme: 4(a)(i) random B1 4(a)(ii) weak / small / negligible B1 4(a)(iii) collide B1 4(a)(iv) decreases B1 4(b)(i) −273 ( C) B1 4(b)(ii) absolute zero B1

This question in 0625/32 May/June 2025

4 (a) Complete the sentences about the kinetic particle model of matter. (i) The movement of the particles in a gas is … … . [1] (ii) The forces between the particles in a gas are … … . [1] (iii) The gas exerts a pressure because the moving gas particles … … . [1] (iv) As the temperature of a fixed volume of gas decreases, the pressure exerted by the gas … . [1] (b) (i) State the value, in degrees Celsius, of the lowest possible temperature. lowest possible temperature = … °C [1] (ii) State the term used for the lowest possible temperature. … [1] [Total: 6]

6 marks

Mark scheme: 4(a)(i) random B1 4(a)(ii) weak / small / negligible B1 4(a)(iii) collide B1 4(a)(iv) decreases B1 4(b)(i) −273 ( C) B1 4(b)(ii) absolute zero B1

This question in 0625/33 May/June 2025

4 (a) A teacher shows the class a demonstration about heat energy and states of matter. The teacher heats a substance. A heater supplies thermal energy at a steady rate. The students measure the temperature of the substance every minute for 30 minutes. Fig. 4.1 shows the graph of their results. At point A, the substance is solid. 200 F 150 temperature D E / °C 100 B C 50 0 A 0 5 10 15 20 25 30 time / min Fig. 4.1 (i) Describe the effect of the thermal energy input in section AB of the graph. … [1] (ii) Describe the effect of the thermal energy input in section BC of the graph. … [1] (iii) Determine the temperature at which the substance boils. … [1] (iv) Deduce the state of matter of the substance in section EF of the graph. … [1] (b) Evaporation is the name of a process that causes puddles of water to dry gradually. (i) Describe the process of evaporation. Use your ideas about particles. … … … … … [3] (ii) Describe another effect that evaporation has on the remaining water in the puddle. … [1] [Total: 8]

8 marks

Mark scheme: 4(a)(i) temperature increasing or internal energy increasing B1 4(a)(ii) melting or changing from solid to liquid B1 4(a)(iii) 140 (°C) B1 4(a)(iv) Gas B1 4(b)(i) any three from the following: B3 • liquid (particles) → gas / vapour (particles) • happens at a surface • (liquid / water absorbs) thermal energy / heat from sun / surroundings / remaining liquid • (average) kinetic energy of particle increases • more energetic particles escape owtte 4(b)(ii) (remaining liquid) cools B1

This question in 0625/33 Oct/Nov 2025