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
51–59 of 59 · Easy
Question 51
2 marks · Easy
Answer and see the solution →Calculate the volume in cm³ of 0.150 mol/dm³ sulfuric acid solution that contains 0.0300 mol of sulfuric acid.
Question 52
2 marks · Easy
Answer and see the solution →Explain why, when rearranging the concentration equation to solve for volume, the number of moles must be divided by concentration, and not the other way around.
Question 53
3 marks · Easy
Answer and see the solution →The following table shows the reaction between sodium sulfate and barium chloride:
Reactant Volume (cm³) Concentration (mol/dm³) Sodium sulfate 50.0 0.100 Barium chloride excess — Use the data given to answer the following:
(a)[1 mark]Calculate the number of moles of sodium sulfate used.
(b)[1 mark]Use the balanced equation to state how many moles of barium sulfate will be formed.
(c)[1 mark]State the minimum volume of sodium sulfate solution (in cm³) needed to ensure 0.0100 mol of barium sulfate forms, using the same concentration.
Question 54
1 mark · Easy
Answer and see the solution →State the information you must know to calculate the volume of a solution required to react with a known amount of another reactant.
Question 55
3 marks · Easy
Answer and see the solution →20.0 cm³ of a solution contains 0.00400 mol of a substance.
(a)[1 mark]Calculate the volume of the solution in dm³.
(b)[1 mark]Calculate the concentration of the solution in mol/dm³.
(c)[1 mark]State the formula used for this calculation.
Question 56
2 marks · Easy
Answer and see the solution →Nitric acid reacts with sodium carbonate according to the following equation:
Calculate the minimum volume, in cm³, of 0.250 mol/dm³ nitric acid solution needed to completely react with 25.0 cm³ of 0.100 mol/dm³ sodium carbonate solution.
Question 57
5 marks · Easy
Answer and see the solution →Ammonia gas is produced by the reaction of hydrogen gas with nitrogen gas at room temperature and pressure (rtp).
(a)[1 mark]State the balanced chemical equation for the formation of ammonia from hydrogen and nitrogen.
(b)[1 mark]What is the volume of 2 moles of hydrogen gas at rtp? Give your answer in dm³.
(c)[1 mark]Convert your answer to part (b) into cm³.
(d)[1 mark]If 1 mole of nitrogen gas reacts completely, how many moles of hydrogen gas are needed?
(e)[1 mark]Calculate the total volume (in dm³) of all gases present after the complete reaction of 1 dm³ nitrogen gas with excess hydrogen gas at rtp. (State your assumptions about volumes in your answer.)
Question 58
5 marks · Easy
Answer and see the solution →A student investigates the reaction between barium hydroxide and sulfuric acid:
(a)[2 marks]Calculate the number of moles of barium hydroxide in 40.0 cm³ of 0.200 mol/dm³ barium hydroxide solution.
(b)[3 marks]During a titration, 25.0 cm³ of the barium hydroxide solution from part (a) is neutralised by 19.5 cm³ of sulfuric acid solution.
Calculate the concentration of the sulfuric acid in mol/dm³. Show your working.
Question 59
5 marks · Easy
Answer and see the solution →Zinc sulfate solution reacts with barium chloride solution: \[ \ce{ZnSO4(aq) + BaCl2(aq) -> BaSO4(s) + ZnCl2(aq)} \] A titration is carried out to determine the amount of barium chloride solution required to completely react with a given volume of zinc sulfate solution.
(a)[1 mark]Write the mole ratio of zinc sulfate to barium chloride in the balanced chemical equation.
(b)[1 mark]In a titration, 30.0 cm³ of 0.150 mol/dm³ zinc sulfate solution reacts exactly with 30.0 cm³ of barium chloride solution. Calculate the number of moles of zinc sulfate used.
(c)[1 mark]Using your answers from (a) and (b), calculate the number of moles of barium chloride that react.
(d)[2 marks]Calculate the concentration (in mol/dm³) of the barium chloride solution.