States of matter — IGCSE Chemistry (0620) questions by topic
Explaining the white cloud that forms where hydrogen chloride and ammonia gases meet, identifying which temperature and pressure combination moves gas particles fastest and furthest apart, and describing what happens to particle movement and collisions as gas pressure falls are the tasks this topic sets, worth 1 to 10 marks across 42 real questions from 2023 to 2025 papers.
Identify, state, name, describe and complete top the command words, and describe here means giving the particle-level behaviour, such as speed or spacing, rather than a macroscopic observation like volume. Because kinetic-particle-theory questions are short but easy to get subtly wrong, working through several and checking each against instant marking is a quick way to confirm particle-level reasoning, not just the final multiple-choice letter, is correct.
May–June 2025, Paper 11
Which process happens when water vapour changes to rain? A boiling B condensing C evaporating D freezing
Answer this question and get it marked →The diagrams show the arrangement of particles in three different states of matter. state 1: particles closely packed in a regular fixed arrangement (a solid). state 2: a few…
Answer this question and get it marked →May–June 2025, Paper 12
Substance L melts at -7 °C and is a brown liquid at room temperature. What is the boiling point of pure L? A -77 °C B -7 °C to +7 °C C 59 °C D 107 °C to 117 °C
Answer this question and get it marked →Which row describes how the volume of a gas changes when its temperature is increased at constant pressure and when its pressure is increased at constant temperature? temperature…
Answer this question and get it marked →Nitrogen dioxide is a red-brown gas which is more dense than air. The diagram shows the arrangement of two gas jars which contain nitrogen dioxide and air separated with a glass…
Answer this question and get it marked →May–June 2025, Paper 13
Liquid iron is cooled to form solid iron. Which statement about the particles in iron is correct? A The particles move further apart. B The particles move faster. C The position…
Answer this question and get it marked →May–June 2025, Paper 21
A gas is placed in a sealed container with a fixed volume. The gas is heated. Which statements are correct? 1. The gas molecules move around faster. 2. The gas particles collide…
Answer this question and get it marked →A sample of ethanol is heated at a constant rate. The heating curve for this sample is shown. The graph plots temperature against time and is labelled with points 1 to 6: point 1…
Answer this question and get it marked →May–June 2025, Paper 22
An ice cube melts. The diagram shows an ice cube changing into a pool of water. What happens to the molecules of water in the ice cube? A They evaporate. B They dissolve. C They…
Answer this question and get it marked →A sample of a liquid, X, is heated to a temperature above its boiling point. X is then cooled, so that it condenses and then freezes. Which graph describes the change in…
Answer this question and get it marked →May–June 2025, Paper 23
Which two changes, when applied at the same time to a fixed amount of gas, cause the greatest increase in volume of the gas? The options give a change in pressure and a change in…
Answer this question and get it marked →Solid G is heated until it melts. It is then left to cool to room temperature. The graph shows the cooling curve for G. The curve shows temperature falling, then a horizontal…
Answer this question and get it marked →May–June 2024, Paper 11
The boiling point of sodium is 890 °C. What happens to sodium atoms as the temperature of a sample of sodium changes from 950 °C to 900 °C? A The atoms move more quickly and bonds…
Answer this question and get it marked →Which row shows the conditions for the particles of a gas colliding most frequently? (columns: pressure, temperature) A high, high B high, low C low, high D low, low
Answer this question and get it marked →May–June 2024, Paper 12
Which statement about gases is correct? A Gases are difficult to compress when pressure is applied. B The particles in gases are close together. C The particles in gases have a…
Answer this question and get it marked →A sample of argon gas is heated in a closed container. Which row describes what happens to the pressure and the size of the argon atoms? (columns: pressure; size) A decreases;…
Answer this question and get it marked →May–June 2024, Paper 13
Which two processes are required to change ice into steam? A boiling and melting B boiling and freezing C condensing and melting D condensing and freezing
Answer this question and get it marked →Which row describes how the volume of a gas changes when the temperature increases, or when the pressure increases? (columns: temperature increases; pressure increases) A volume…
Answer this question and get it marked →May–June 2024, Paper 21
A gas is heated. The pressure is kept constant. Which statement describes the behaviour of the particles in the gas? A The particles move faster and become closer together. B The…
Answer this question and get it marked →A mixture of ice and water is left to stand and the ice melts. Which row describes what happens as the ice is melting? (columns: temperature of mixture; energy change) A…
Answer this question and get it marked →Hydrogen chloride gas [Mr: HCl, 36.5] is released at P in the apparatus shown; the universal indicator paper turns red after 38 s. The experiment is repeated using sulfur dioxide…
Answer this question and get it marked →May–June 2024, Paper 22
Which gas has the slowest rate of diffusion? A H2 B NH3 C CH4 D CO2
Answer this question and get it marked →May–June 2024, Paper 23
Sodium chloride is a liquid at 900 °C. Which row describes the arrangement and the motion of the particles in sodium chloride at 900 °C? (columns: arrangement of particles; motion…
Answer this question and get it marked →Hydrogen chloride gas, HCl, reacts with ammonia gas, NH3, to form solid ammonium chloride. In a tube with a source of hydrogen chloride gas at one end and a source of ammonia gas…
Answer this question and get it marked →October–November 2024, Paper 11
The table shows the melting and boiling points of four elements. Which element is a gas at room temperature and pressure? melting point / °C boiling point / °C --- --- --- A -101…
Answer this question and get it marked →Four statements about the arrangement or movement of particles are given. 1 Particles are packed in a regular arrangement. 2 Particles are randomly arranged. 3 Particles move over…
Answer this question and get it marked →October–November 2024, Paper 12
The table shows some information about the three states of matter. particle separation particle arrangement type of motion --- --- --- --- 1 touching with some particles having…
Answer this question and get it marked →A diagram shows changes of state between solid, liquid and gas, with arrows A and B pointing from liquid to gas and C and D pointing the other way. Which arrow represents…
Answer this question and get it marked →In which states of matter does diffusion occur readily? A gases and liquids B gases only C liquids and solids D solids only
Answer this question and get it marked →October–November 2024, Paper 13
Which conditions cause gas particles to move the fastest and the furthest apart? temperature pressure --- --- --- A high high B low high C high low D low low
Answer this question and get it marked →Which statement describes a liquid at room temperature? A A sample of a liquid has a fixed volume and shape. B A sample of a liquid does not have a fixed volume or shape. C The…
Answer this question and get it marked →A compound, X, has a melting point of 71 °C and a boiling point of 375 °C. Which statement about X is correct? A It is a liquid at 52 °C and a gas at 175 °C. B It is a liquid at…
Answer this question and get it marked →October–November 2024, Paper 21
Which row describes the arrangement and motion of the particles in a liquid? arrangement motion --- --- --- A random and particles are touching moving slowly B random with space…
Answer this question and get it marked →October–November 2024, Paper 22
Oxygen melts at -219 °C and boils at -183 °C. At which temperature is oxygen a liquid? A -225 °C B -189 °C C -175 °C D 25 °C
Answer this question and get it marked →The pressure of a sample of gas is decreased. The temperature is kept constant. Which row describes the effects on the particles? movement of particles collisions between…
Answer this question and get it marked →October–November 2024, Paper 23
A sample of ethanol is left in an open beaker at room temperature. After 24 hours, no ethanol remains in the beaker. What has happened to the ethanol? A It has boiled. B It has…
Answer this question and get it marked →A gas is in a sealed container with a fixed volume. Which statements describe what happens to the molecules in the gas when the temperature is increased? 1 They move more slowly.…
Answer this question and get it marked →October–November 2024, Paper 32
This question is about acids, bases and salts. Crystals of zinc sulfate are made by warming excess solid zinc with dilute sulfuric acid: Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2O(l).…
Answer this question and get it marked →October–November 2024, Paper 33
This question is about acids, bases and salts. Crystals of zinc chloride can be made by warming excess solid zinc oxide with dilute hydrochloric acid: ZnO(s) + 2HCl(aq) →…
Answer this question and get it marked →October–November 2023, Paper 31
Bromine is a liquid at room temperature. State two general properties of a liquid.
Answer this question and get it marked →October–November 2023, Paper 32
Tin is a solid at room temperature. State two general properties of a solid.
Answer this question and get it marked →October–November 2023, Paper 33
Nitrogen is a gas at room temperature. State two general properties of a gas.
Answer this question and get it marked →Other IGCSE Chemistry topics
- Organic chemistry (155)
- The Periodic Table (102)
- Metals (96)
- Acids, bases and salts (84)
- Experimental techniques and chemical analysis (84)
- Chemical reactions (80)
- Stoichiometry (62)
- Chemical bonding (58)
- Chemistry of the environment (55)
- Atoms, elements and compounds (51)
- Electrochemistry (47)
- Practical skills (43)