Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Simple differences between mixtures and compounds
19 practice questions
Practice questions
1–3 of 3 · Hard
Question 1
2 marks · Hard
Answer and see the solution →A student is given three samples: Sample A contains only carbon atoms, Sample B contains molecules of carbon dioxide, and Sample C contains both carbon dioxide and oxygen gas mixed together. Classify each sample as an element, a compound, or a mixture.
Question 2
5 marks · Hard
Answer and see the solution →A researcher is investigating two samples: Sample X is a pure substance, and Sample Y is a mixture. She records the melting and boiling behaviour of each sample while heating.
(a)[2 marks]Describe the expected melting behaviour of Sample X and Sample Y as they are heated.
(b)[2 marks]Explain how boiling point data can be used to decide whether Sample X or Sample Y is pure or a mixture.
(c)[1 mark]A sample melts sharply at 801°C and boils at exactly 1465°C with no temperature change during the phase transitions. State whether it is pure or a mixture, and justify your answer with evidence from the data.
Question 3
2 marks · Hard
Answer and see the solution →Give one way in which the proportions of substances in a mixture are different from those in a compound. Use an example to support your answer.