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
41–50 of 144
Question 41
2 marks · Easy
Answer and see the solution →Calculate the number of moles of helium gas in a 12 dm³ container at room temperature and pressure.
Question 42
2 marks · Easy
Answer and see the solution →Explain why the volume of gas collected must be converted to dm³ before using the molar volume of 24 dm³ in calculations.
Question 43
3 marks · Easy
Answer and see the solution →The table shows the volume of a gas produced from the reaction of different masses of magnesium with excess hydrochloric acid at room temperature and pressure.
Mass of magnesium (g) Volume of H₂ gas (dm³) 0.12 0.12 0.24 0.24 0.36 0.36 (a)[1 mark]Describe the relationship between the mass of magnesium and the volume of hydrogen gas produced.
(b)[1 mark]Suggest the volume of hydrogen gas (in dm³) produced from 0.48 g of magnesium.
(c)[1 mark]Explain your answer to part (b).
Question 44
1 mark · Easy
Answer and see the solution →Write the formula relating number of moles, volume of gas (in dm³), and molar volume at room temperature and pressure.
Question 45
3 marks · Easy
Answer and see the solution →(a)Potassium reacts with water to produce potassium hydroxide and hydrogen gas according to:
If 4.6 g of potassium (Ar: K = 39) reacts completely, calculate:
(i)[1 mark]the number of moles of potassium reacted.
(ii)[1 mark]the number of moles of hydrogen gas formed.
(iii)[1 mark]the volume of hydrogen gas produced at rtp (in dm³).
Question 46
2 marks · Easy
Answer and see the solution →Calculate the volume in cm³ of 0.015 mol of nitrogen gas at room temperature and pressure.
Question 47
2 marks · Normal
Answer and see the solution →Calculate the volume, in cm³, of 0.16 g of oxygen gas (O₂) at room temperature and pressure. (Ar: O = 16; molar volume = 24,000 cm³ at rtp)
Question 48
4 marks · Normal
Answer and see the solution →Hydrochloric acid reacts with sodium carbonate to produce sodium chloride, carbon dioxide and water. The balanced equation is:
(a)[2 marks]Calculate the number of moles in 1.06 g of sodium carbonate. (Ar: Na = 23, C = 12, O = 16)
(b)[2 marks]Calculate the volume, in dm³, of carbon dioxide produced at rtp by this mass of sodium carbonate. (Molar volume at rtp = 24 dm³)
Question 49
3 marks · Normal
Answer and see the solution →Calculate the number of moles in 360 cm³ of nitrogen gas at room temperature and pressure. Give your answer to two decimal places. (Molar volume = 24,000 cm³ at rtp)
Question 50
3 marks · Normal
Answer and see the solution →A student needs to calculate the mass of carbon dioxide produced when 48,000 cm³ of carbon dioxide is collected at room temperature and pressure. Explain the steps, including the formulae needed, to calculate the mass of carbon dioxide produced. (Ar: C = 12, O = 16; molar volume = 24,000 cm³ at rtp)