Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Chemical Formulae, Equations and Calculations Part 2
144 practice questions
Topics covered
- Calculations involving gas volumes19 practice questions
- Calculating the volume of a certain number of moles19 practice questions
- Using the molar volume in calculations with chemical equations19 practice questions
- Concentrations of solutions19 practice questions
- Calculations with equations involving solutions19 practice questions
- The standard calculation19 practice questions
- Reversing the calculations20 practice questions
Practice questions
1–10 of 144
Question 1
1 mark · Easy
Answer and see the solution →State the volume, in dm³, occupied by one mole of any gas at room temperature and pressure (rtp).
Question 2
3 marks · Easy
Answer and see the solution →Hydrogen peroxide decomposes to form water and oxygen gas as shown:
(a)[1 mark]Write the stoichiometric ratio between hydrogen peroxide and oxygen in the equation above.
(b)[2 marks]Calculate the volume, in dm³, of oxygen gas produced at rtp from complete decomposition of 0.50 mol of hydrogen peroxide.
Question 3
2 marks · Easy
Answer and see the solution →Calculate the volume, in dm³, of 0.75 moles of carbon dioxide gas at room temperature and pressure (rtp).
Question 4
3 marks · Easy
Answer and see the solution →A student collects three different gases at rtp in three identical flasks. Data for the gases is shown below:
Volumes and types of gas collected at rtp Gas Volume collected (dm³) Moles collected Argon 1.0 ? Oxygen 0.5 ? Hydrogen 2.0 ? (a)[1 mark]Calculate the number of moles of argon collected.
(b)[1 mark]Calculate the number of moles of oxygen collected.
(c)[1 mark]Which gas sample contains the largest number of molecules? Explain your answer.
Question 5
1 mark · Easy
Answer and see the solution →What is the formula used to calculate the volume of a given amount of gas, in moles, at rtp?
Question 6
3 marks · Easy
Answer and see the solution →Methane combusts in oxygen according to the equation:
A sample of methane of volume 2.4 dm³ is burned completely in excess oxygen at rtp.
(a)[1 mark]Calculate the number of moles of methane in the sample.
(b)[2 marks]Calculate the volume, in dm³, of carbon dioxide gas produced at rtp.
Question 7
2 marks · Easy
Answer and see the solution →Calculate the volume, in dm³, of 3.0 moles of nitrogen gas at room temperature and pressure (rtp).
Question 8
2 marks · Easy
Answer and see the solution →Two balloons are filled with different gases at room temperature and pressure (rtp): one has 48 dm³ of helium (He), and the other has 48 dm³ of methane (CH₄).
Explain whether the two balloons contain the same number of particles. Give a reason for your answer.
Question 9
2 marks · Normal
Answer and see the solution →Calculate the volume, in dm³, of 0.25 moles of nitrogen gas, N₂, at room temperature and pressure (rtp).
Question 10
4 marks · Normal
Answer and see the solution →Calcium carbonate reacts with hydrochloric acid as shown in the equation:
(a)[2 marks]State the volume of carbon dioxide gas produced (in cm³ at rtp) from 0.10 mol of calcium carbonate.
(b)[2 marks]Give one reason why the actual volume of gas collected might be less than the calculated value.