Titration

Evaluation of procedures:

|Precision |The precision of each of the measurements you made is indicated by the % uncertainty calculated. |
|Accuracy |The accuracy of an overall result (concentration of acid) means how close it is to the ‘true’ value. |
| |It is possible to make very precise measurements but still end up with an inaccurate result because of a weakness |
| |in the procedure. |
|Reliable |You repeat measurements and if they are close then they are said to be reliable. A single measurement could be an |
| |outlier. |
|Limitation |This is a stage in the procedure which could have led to an inaccuracy in the overall result (concentration of |
| |acid). |

A little book of tips for titrations.

• Recording results • Calculating the average titre • Evaluation of results • Evaluation of procedures

Recording results and calculating the average/mean titre:

|Titration |Rough |1 |2 |3 |4 |5 |
|Initial burette reading/cm3 |0.00 |22.00 |1.00 | | | |

Average titre = 21.85 + 21.95 / 2 = 21.90 (quote to 2 decimal places)

Titration |Rough |1 |2 |3 |4 |5 | |Final burette reading/cm3 |22.00 |43.85