A technician carries out a titration to check a cleaning solution. The table shows the burette readings.
| Titration | Rough | 1 | 2 | 3 | 4 |
|---|---|---|---|---|---|
| Initial burette reading (cm3\mathrm{cm^{3}}cm3) | 0.10 | 0.35 | 1.20 | 4.60 | 2.15 |
| Final burette reading (cm3\mathrm{cm^{3}}cm3) | 26.90 | 26.50 | 27.40 | 30.85 | 28.60 |
Calculate the mean titre the technician should use.
Explain whether the technician needs to repeat the titration before using this mean.
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.