Titrations - Analysis: Percent Error Calculation

Percent error is determined by taking the absolute value of the difference between the actual and experimental values, divided by the actual value, times 100 to make it a percent. In the titration experiment, the molarity of the base was calculated to be 0.18 M. The actual concentration of the base is 0.20 M. Therefore the percent error is 10%. One way to ensure the correct molarity is to repeat several trials of the titration and to take an average of the trials. There are also several sources of error: the buret could have been read incorrectly, there could be water in the buret, there could be contamination, and the pink could not be pale enough.