We have been told to carry out the following and then evaluate but I have some questions that I think might be in the evaluation. I would be ever so grateful.
We are reacting ethanol and ethanoic acid and determining the Kc by doing a titration with sodium hydroxide.
1. As we have added a catalyst how do we remove this from the working
2. Why would we use phenolphthalein and why does its go back colourless after the end point
3. Why is the preferred catalyst sulphuric acid
4. When transferring the equilibrium mixture from a tube to a flask we washing twice and add washings
5. Why would be make the solution up to 250cm3 using distilled water
6. Once the mixture is made up to 250cm3, why do we shake thoroughly
7. Why might two layers appear when shaking the mixture in with distilled water, plus why is it important to prevent this
8. Why would we rinse a pipette with the diluted equilibrium mixture before using the pipette to transfer 25cm3 of the mixture
9. Why would we rinse the burette with sodium hydroxide before filling it with sodium hydroxide and carrying out the titration
10. Why is it important to have a minimum of two concordant titres, and why should we ignore anomalies
11. What are the main errors from titrations?