A student titrates 25.0 cm3\mathrm{cm^{3}}cm3 portions of sodium hydroxide solution with 0.0500 mol/dm3\mathrm{mol/dm^{3}}mol/dm3 sulfuric acid.
H2SO4+2NaOH→Na2SO4+2H2O \mathrm{H_{2}SO_{4} + 2NaOH \rightarrow Na_{2}SO_{4} + 2H_{2}O} H2SO4+2NaOH→Na2SO4+2H2O| Titration | Rough | 1 | 2 | 3 |
|---|---|---|---|---|
| Titre (cm3\mathrm{cm^{3}}cm3) | 21.20 | 19.95 | 20.60 | 20.05 |
The student uses the mean of the concordant titres.
What is the concentration of the sodium hydroxide solution?
0.0400 mol/dm3\mathrm{mol/dm^{3}}mol/dm3
0.0800 mol/dm3\mathrm{mol/dm^{3}}mol/dm3
0.0808 mol/dm3\mathrm{mol/dm^{3}}mol/dm3
0.0818 mol/dm3\mathrm{mol/dm^{3}}mol/dm3
152 exam-style questions on OCR GCSE Chemistry 5.1 Monitoring chemical reactions, covering 5.1.1 The technique of titration, 5.1.2 Theoretical mass, percentage yield and atom economy, 5.1.3 Concentration of a solution in mol/dm3, 5.1.4 Concentration calculations and titration results, 5.1.5 Molar gas volume and volumes of gases in reactions, and 5.1.6 Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.