A student performs a titration five times to determine the volume of standard sodium carbonate solution required to neutralise a sample of hydrochloric acid. Their burette readings are recorded in the table below.
| Rough | Titration 1 | Titration 2 | Titration 3 | Titration 4 | |
|---|---|---|---|---|---|
| Final reading (cm3\text{cm}^3cm3) | 25.90 | 24.85 | 48.95 | 24.60 | 49.30 |
| Initial reading (cm3\text{cm}^3cm3) | 0.80 | 0.60 | 25.10 | 0.30 | 25.10 |
What is the mean volume of sodium carbonate solution that the student should use for subsequent concentration calculations?
24.15 cm324.15\text{ cm}^324.15 cm3
24.25 cm324.25\text{ cm}^324.25 cm3
24.34 cm324.34\text{ cm}^324.34 cm3
24.28 cm324.28\text{ cm}^324.28 cm3
119 exam-style questions on Edexcel GCSE Chemistry 6.2 Quantitative analysis, covering 6.2.1 Concentration in mol dm⁻³ and titration calculations, 6.2.2 Percentage yield and why actual yield falls short, 6.2.3 Atom economy of a reaction, 6.2.4 Choosing a reaction pathway, and 6.2.5 Molar volume of gases and Avogadro's law. Each one has a worked solution and a mark scheme showing where the marks go.