Simple acid-base titration can be used to find out the concentration of a solution

Running a titration experiment

This video by the Royal Society of Chemistry explains the steps involved in running a titration experiment. Fran demonstrates how to rinse and prepare the burette to ensure accurate results. The acid-base titration uses a standard solution of Na2CO3 to find the exact concentration of HCl by identifying the end-point of the neutralisation reaction. The video includes both a rough titration and recording data from a subsequent accurate titration. Calculations of the concentration of HCl are not included, so students could follow up with data analysis to assess their understanding of the content. 

Results analysis

Students can be given typical results such as these (taken from the AQA AS and A Level Required Practical Handbook), and asked to manipulate and analyse them. Students do not need to be provided with a complete table as they could be expected to calculate the titre from the final and initial readings. They should also be able to identify concordant results and discard anomalous results before continuing with their analysis.

Titration Rough   1    2   3 
 Final reading  24.20 47.40 24.10  47.35 
Initial reading   0.35 24.20  0.65 24.10
Titre / cm3  23.85 23.20  23.45  23.25 

AQA required practical specification

Mrs Peers-Dent from Malmesbury Education carries out the titration in this video, following the AQA required practical specification. It demonstrates how the titration procedure can be used to find the concentration of H2SO4 using a known concentration of NaOH. Mrs Peers-Dent measures the acid to the nearest 0.1cm3, whereas in the Royal Society of Chemistry video above Fran measures to the nearest 0.05cm3. The titration screen experiment below also measures to the nearest 0.05cm3. You may decide which is the most appropriate based on the ability of the group you are working with or you could use this as an opportunity to discuss key terminology such as precision, accuracy and reliability.

Simulation

Learners can practise their skills using Royal Society of Chemistry’s titration screen experiment. We recommend that 14–16 students complete Level 1 of the screen experiment, while older students can progress to Levels 2, 3 and 4. The screen experiments frame the titration procedure with a real-world scenario to foster an interest in chemistry careers and contextualise their learning.

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