Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
21–30 of 991
Question 21
3 marks · Easy
Answer and see the solution →A block of ice is left at room temperature. It changes from a solid to a liquid and then to a gas.
(a)[1 mark]Name the process when ice changes from solid to liquid.
(b)[1 mark]Name the process when water changes from liquid to gas.
(c)[1 mark]Describe what happens to the movement of particles during melting and boiling.
Question 22
2 marks · Easy
Answer and see the solution →Carbon dioxide can change directly from a solid to a gas and back again. Explain the names given to each of these two processes.
Question 23
3 marks · Easy
Answer and see the solution →The table below shows the temperature changes as substance X is heated at a steady rate. The melting point of X is 12°C and the boiling point is 65°C.
Time (min) Temperature (°C) 0 5 3 11 6 12 9 30 12 50 15 65 18 70 (a)[1 mark]At what time does substance X start to melt?
(b)[1 mark]At what temperature does X start to boil?
(c)[1 mark]Explain, using particle theory, what happens to the particles of X as it melts.
Question 24
1 mark · Easy
Answer and see the solution →Name the process by which water vapour turns into liquid water.
Question 25
3 marks · Easy
Answer and see the solution →The diagram below represents the arrangement of particles in a solid, a liquid, and a gas.
Particle arrangements in three states of matter. (a)[1 mark]Describe the arrangement of particles in the solid region.
(b)[1 mark]Describe the arrangement of particles in the gas region.
(c)[1 mark]Explain how the differences in particle arrangement relate to the three states of matter.
Question 26
2 marks · Easy
Answer and see the solution →When a solid substance is heated from 10 °C to 70 °C, it melts completely at 50 °C. Use particle theory to calculate the number of changes of state that take place as the temperature increases from 10 °C to 70 °C.
Question 27
2 marks · Easy
Answer and see the solution →Water freezes at 0 °C and boils at 100 °C. Calculate the number of different state interconversion processes that water can undergo in this temperature range. (Name each process as part of your answer.)
Question 28
2 marks · Normal
Answer and see the solution →Explain why the particles in a liquid are able to move past each other, while the particles in a solid cannot.
Question 29
4 marks · Normal
Answer and see the solution →The diagram below shows a substance being heated until it completely changes from solid to gas.
(a)[1 mark]State the name of the process occurring as the solid changes directly to a gas.
(b)[2 marks]Describe what happens to the arrangement and movement of the particles during this process.
(c)[1 mark]Name the reverse process (gas to solid) and give one example of a substance that sublimates.
Question 30
3 marks · Normal
Answer and see the solution →Ammonium chloride can change directly from a solid to a gas when heated. Explain why the process observed is called sublimation, and describe what happens to the particles during this process.