An analytical chemist is performing a titration to determine the exact concentration of citric acid in a sample of lime juice. They use a volumetric pipette to transfer 20.0 cm3 of the lime juice into a conical flask and fill a burette with a standard 0.100 mol dm-3 potassium hydroxide solution.
Explain two practical steps (excluding the initial rinsing and calibration of the apparatus) that the chemist should perform during the titration to ensure that an accurate titre volume of potassium hydroxide is obtained. For each step, explain why it improves the accuracy of the result.
Practise Edexcel GCSE Chemistry Quantitative analysis 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.