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 24 · Hard
Question 1
2 marks · Hard
Answer and see the solution →A sealed glass tube at rtp contains 0.42 moles of sulfur dioxide gas, SO₂. Calculate the volume, in dm³, of sulfur dioxide gas in the tube at rtp.
Question 2
5 marks · Hard
Answer and see the solution →Zinc reacts with dilute sulfuric acid to produce hydrogen gas according to the equation:
(a)[1 mark]State the volume, in dm³, occupied by 1 mole of hydrogen gas at rtp.
(b)[2 marks]Calculate the number of moles of hydrogen produced when 3.9 g of zinc reacts completely with excess sulfuric acid.
(Relative atomic mass: Zn = 65.)
(c)[2 marks]Calculate the volume, in dm³, of hydrogen gas produced at rtp from part (b).
Question 3
2 marks · Hard
Answer and see the solution →A sample of carbon monoxide, CO, has a volume of 6.0 dm³ at rtp. Calculate the number of moles of CO in the sample. Show your working.
Question 4
2 marks · Hard
Answer and see the solution →State the volume, in dm³ and in cm³, that 1 mole of a gas would occupy at room temperature and pressure (rtp).
Question 5
5 marks · Hard
Answer and see the solution →A student reacts zinc with dilute hydrochloric acid to produce hydrogen gas at room temperature and pressure (rtp), according to the equation:
The student collects exactly 0.85 mol of hydrogen gas.
(a)[2 marks]Calculate the volume, in dm³, of 0.85 mol of hydrogen gas at rtp. Show your working.
(b)[1 mark]Convert your answer from part (a) into cm³.
(c)[2 marks]Explain why a different gas produced under the same conditions and with the same number of moles would occupy the same volume.
Question 6
2 marks · Hard
Answer and see the solution →A laboratory sample has a measured volume of 0.275 dm³. Convert this volume to cm³, showing your working.
Question 7
2 marks · Hard
Answer and see the solution →A student collects 8.4 g of oxygen gas at room temperature and pressure (rtp). Calculate the volume, in dm³, of this oxygen gas. (Ar: O = 16; molar volume = 24 dm³ at rtp.)
Question 8
5 marks · Hard
Answer and see the solution →When sodium nitrate (ce{NaNO3}) decomposes on heating, it produces sodium nitrite (ce{NaNO2}) and oxygen gas (ce{O2}). The equation is:
(a)[2 marks]Calculate the number of moles in 0.34 g of sodium nitrate. (Ar: Na = 23, N = 14, O = 16)
(b)[3 marks]Use your answer to (a) to calculate the volume, in cm³, of oxygen gas produced at rtp.
(Molar volume = 24,000 cm³ at rtp.)
Question 9
2 marks · Hard
Answer and see the solution →Calculate the number of moles of neon gas present in a 4.8 dm³ flask at room temperature and pressure. Give your answer to two decimal places. (Molar volume = 24 dm³ at rtp.)
Question 10
2 marks · Hard
Answer and see the solution →A laboratory technician needs to prepare 400 cm³ of a potassium nitrate (KNO₃) solution with a concentration of 0.125 mol/dm³. Calculate the amount, in mol, of potassium nitrate required. Give your answer to 2 decimal places.