To determine the exact volume of dilute nitric acid required to neutralise 25.0 cm3 of potassium hydroxide solution, a student performs a titration. Table 1 shows the results of the four titrations carried out.
Table 1
| Titration 1 (Rough) | Titration 2 | Titration 3 | Titration 4 | |
|---|---|---|---|---|
| Final burette reading / cm3\text{cm}^3cm3 | 25.30 | 25.10 | 24.10 | 26.15 |
| Initial burette reading / cm3\text{cm}^3cm3 | 0.50 | 1.20 | 0.00 | 2.15 |
| Volume of acid used / cm3\text{cm}^3cm3 | 24.80 | 23.90 | 24.10 | 24.00 |
In this analysis, concordant results are defined as volumes of acid used that are within 0.20 cm3 of each other.
Calculate the mean volume of nitric acid required, using only the concordant results.
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.