Unit 1: Structure 1: Models of the Particulate Nature of Matter
Topic 1.4: Counting Particles by Mass: The Mole Questions
Practice 20 exam-style questions for IB Chemistry Topic 1.4. Review the question stems below, then unlock the full Question Bank to access markschemes, model answers, and AI grading.
1Determine2 marks
A hydrocarbon has the empirical formula CH and a relative molecular mass of 78.
Determine its molecular formula.
(Empirical formula mass of CH = 13.02.) [2]
Determine its molecular formula.
(Empirical formula mass of CH = 13.02.) [2]
Markscheme and model answer locked
Unlock Question2State1 mark
2026
State what is meant by the empirical formula of a compound.
Markscheme and model answer locked
Unlock Question3State1 mark
2026
State the units of concentration when a solution is described in mol dm⁻³.
Markscheme and model answer locked
Unlock Question4Calculate2 marks
A 5.85 g sample of sodium chloride, NaCl, is weighed out.
Calculate the amount, in moles, present.
(M(NaCl) = 58.44 g mol⁻¹.)
Calculate the amount, in moles, present.
(M(NaCl) = 58.44 g mol⁻¹.)
Markscheme and model answer locked
Unlock Question5Draw1 mark
2026
Draw a diagram showing how the meniscus should be read in a volumetric flask.
Markscheme and model answer locked
Unlock Question6Draw1 mark
2026
Draw a possible structural formula for this compound.
Markscheme and model answer locked
Unlock Question7explain3 marks
Explain the difference between an empirical and a molecular formula, and state what extra information is needed to convert one into the other.
Markscheme and model answer locked
Unlock Question8determine2 marks
A hydrocarbon has the empirical formula C₂H₅ and a relative molecular mass of 58. Determine its molecular formula.
Markscheme and model answer locked
Unlock Question9determine3 marks
0.500 g of a metal oxide contains 0.400 g of the metal M, whose molar mass is 55.85 g mol⁻¹. Determine the empirical formula of the oxide.
Markscheme and model answer locked
Unlock Question10calculate2 marks
Calculate the amount, in mol, represented by 3.01 × 10²³ atoms of carbon. (L = 6.02 × 10²³ mol⁻¹)
Markscheme and model answer locked
Unlock Question11calculate2 marks
Calculate the mass of 0.250 mol of sodium chloride, NaCl. (M: Na 22.99, Cl 35.45)
Markscheme and model answer locked
Unlock Question12calculate3 marks
Calculate the number of molecules in 10.0 g of carbon dioxide. (M(CO₂) = 44.01 g mol⁻¹, L = 6.02 × 10²³ mol⁻¹)
Markscheme and model answer locked
Unlock Question13define3 marks
Define relative atomic mass and explain why the relative atomic mass of chlorine is 35.45 rather than a whole number.
Markscheme and model answer locked
Unlock Question14calculate2 marks
Calculate the amount, in mol, of sodium chloride in 40.0 cm³ of a 0.250 mol dm⁻³ solution.
Markscheme and model answer locked
Unlock Question15calculate3 marks
Calculate the mass, in g, of sodium chloride (M = 58.44 g mol⁻¹) needed to make 250 cm³ of a 0.150 mol dm⁻³ solution.
Markscheme and model answer locked
Unlock Question16calculate2 marks
25.0 cm³ of 0.500 mol dm⁻³ hydrochloric acid is diluted with water to a total volume of 250.0 cm³. Calculate the concentration of the diluted solution.
Markscheme and model answer locked
Unlock Question17outline3 marks
A student needs 500 cm³ of 0.100 mol dm⁻³ potassium nitrate solution. Outline the steps for preparing it accurately from the solid using a volumetric flask.
Markscheme and model answer locked
Unlock Question18determine3 marks
A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen by mass. Determine its empirical formula. (M: C 12.01, H 1.01, O 16.00)
Markscheme and model answer locked
Unlock Question19Calculate2 marks
Calculate the mass of glucose, C₆H₁₂O₆, needed to prepare 250.0 cm³ of a 0.100 mol dm⁻³ solution.
(M = 180.18 g mol⁻¹.) [2]
(M = 180.18 g mol⁻¹.) [2]
Markscheme and model answer locked
Unlock Question20Calculate2 marks
A 25.0 cm³ sample of 0.480 mol dm⁻³ copper(II) sulfate solution is diluted with water to a total volume of 200.0 cm³.
Calculate the concentration of the diluted solution. [2]
Calculate the concentration of the diluted solution. [2]
Markscheme and model answer locked
Unlock QuestionReady to practice Topic 1.4?
Get instant AI feedback on your answers, view detailed markschemes, and track your progress across all IB Chemistry topics.