States of matter — IGCSE Chemistry (0971) questions by topic
States of matter questions test particle-model reasoning: predicting how a red-brown, denser-than-air gas such as nitrogen dioxide behaves when separated from air by a glass plate, identifying what happens to water molecules as an ice cube melts, working out which statements about heated gas particles in a sealed container are correct, and matching particle-arrangement diagrams to solid, liquid and gas states. Identify, predict and state all want precise particle-behaviour answers rather than general description.
9 questions sit on this page, drawn from papers set between 2023 and 2025, each worth exactly 1 mark. Because every question here is a one-mark multiple-choice item, submitting an answer for instant marking is a quick, low-stakes way to check whether the particle-model reasoning behind a choice, such as gaining energy rather than losing it during melting, is actually correct rather than just familiar-sounding.
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 shows particles closely packed in a random arrangement (a liquid); state 2 shows a few…
Answer this question and get it marked →May–June 2025, Paper 12
Substance L melts at -7 degC and is a brown liquid at room temperature. What is the boiling point of pure L? A -77 degC B -7 degC to +7 degC C 59 degC D 107 degC to 117 degC
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 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 curve plots temperature (y-axis) against time (x-axis) with six labelled points:…
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 2023, Paper 11
The diagram shows the result of dropping a purple crystal into water: a purple crystal in water turns into a purple solution after five hours. Which processes take place in this…
Answer this question and get it marked →Other IGCSE Chemistry topics
- Organic chemistry (31)
- The Periodic Table (29)
- Metals (23)
- Experimental techniques and chemical analysis (19)
- Chemical reactions (14)
- Acids, bases and salts (14)
- Chemical bonding (11)
- Stoichiometry (11)
- Chemistry of the environment (10)
- Electrochemistry (9)
- Atoms, elements and compounds (8)
- Chemical energetics (8)