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
91–100 of 144
Question 91
2 marks · Normal
Answer and see the solution →Calculate the number of moles of copper(II) sulfate in 200 cm³ of solution with concentration 0.050 mol/dm³.
Question 92
4 marks · Normal
Answer and see the solution →Potassium permanganate reacts with iron(II) sulfate as shown:
(a)[2 marks]Calculate the number of moles of FeSO₄ in 50 cm³ of 0.20 mol/dm³ solution.
(b)[2 marks]Use the equation to find the number of moles of KMnO₄ needed to react with this amount of FeSO₄.
Question 93
2 marks · Hard
Answer and see the solution →Sodium carbonate reacts with hydrochloric acid according to the following equation:
If 0.06 mol of hydrochloric acid, HCl, are used in the reaction, calculate the number of moles of sodium carbonate, Na2CO3, that will completely react.
Question 94
5 marks · Hard
Answer and see the solution →Ethanoic acid reacts with sodium hydroxide as follows:
A student mixes 30 cm³ of 0.40 mol/dm³ ethanoic acid with excess sodium hydroxide.
(a)[2 marks]Calculate the number of moles of ethanoic acid used.
(b)[3 marks]Calculate the mass of sodium acetate (CH₃COONa) produced. (Relative formula mass: CH₃COONa = 82)
Question 95
2 marks · Hard
Answer and see the solution →Calculate the number of moles of sulfuric acid, H₂SO₄, in 75 cm³ of solution with concentration 0.20 mol/dm³.
Question 96
1 mark · Easy
Answer and see the solution →State the first step you should always take when calculating the concentration of a solution using the three-step titration calculation method.
Question 97
3 marks · Easy
Answer and see the solution →A student is titrating 25.0 cm³ of sodium hydroxide solution with hydrochloric acid. The concentration of sodium hydroxide is 0.200 mol/dm³.
(a)[2 marks]Calculate the number of moles of sodium hydroxide in 25.0 cm³.
(b)[1 mark]State the equation you would use for this calculation.
(c)[0 marks]Give the unit for the concentration used in the calculation.
Question 98
2 marks · Easy
Answer and see the solution →The equation for the reaction is:
In a titration, 35.0 cm³ of 0.300 mol/dm³ potassium hydroxide are used. Calculate the number of moles of sulfuric acid that will react with this amount, using the equation.
Question 99
2 marks · Easy
Answer and see the solution →Explain, using the three-step titration calculation method, how you can find the concentration of an unknown acid after titrating it with a solution of known concentration.
Question 100
3 marks · Easy
Answer and see the solution →A student has the following titration results:
Titration Volume of NaOH (cm³) Concentration of NaOH (mol/dm³) 1 22.0 0.150 2 21.5 0.150 3 (repeat) 21.7 0.150 The student used 25.0 cm³ of hydrochloric acid of unknown concentration each time. Use the results to calculate the mean number of moles of sodium hydroxide used to neutralise the acid.