A technician uses 0.0400 mol/dm30.0400\,\mathrm{mol/dm^{3}}0.0400mol/dm3 nitric acid to determine the concentration of a calcium hydroxide solution.
In each titration, the technician uses 25.0 cm325.0\,\mathrm{cm^{3}}25.0cm3 of the calcium hydroxide solution.
2HNO3+Ca(OH)2→Ca(NO3)2+2H2O \mathrm{2HNO_{3} + Ca(OH)_{2} \rightarrow Ca(NO_{3})_{2} + 2H_{2}O} 2HNO3+Ca(OH)2→Ca(NO3)2+2H2OAfter a rough titration, the technician records these results.
| Titration | Initial burette reading in cm3\mathrm{cm^{3}}cm3 | Final burette reading in cm3\mathrm{cm^{3}}cm3 |
|---|---|---|
| 1 | 0.50 | 22.95 |
| 2 | 22.95 | 45.45 |
| 3 | 0.10 | 22.85 |
Calculate the concentration of the calcium hydroxide solution in mol/dm3\mathrm{mol/dm^{3}}mol/dm3.
Concentration = ...... 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.