Analysis/Conclusion:
The purpose of this lab was to determine how fast is "fast" for a chemical reaction.
During this lab, the rate constants of crystal violet and sodium hydroxide solutions at various concentrations were calculated. An automatic titrator, red tide machine, and data collection system were used to generate titration curves, and thus calculate the rate constant. The titration curves of three separate solutions were plotted on a graph of ln [CV+] vs. time, and the slopes of each curve were used to determine the rate constant of the given solution. Using the equation for rate constant (k= k'/[OH-]), the average rate constant of the reaction was found to be 0.0101 M^(-1) s^(-1).
During this lab, as in any lab, the possibility for error was inevitable. For example, the crystal violet reacts very quickly when added to the sodium hydroxide. If the solution was not quickly mixed and inserted into the red tide machine, the solution may have begun to react, leading to an inaccurate titration curve and concentration value. Also, if the data collection system was not set-up properly, an inaccurate titration curve would be generated, resulting in the incorrect calculation of concentration. Since the red tide machine was new to many students within the lab, set-up took longer than expected, resulting in rushed and possibly error-filled titrations. In future labs, I would emphasize the importance of mixing solutions quickly to preserve results, and the proper set-up of data collection systems, in order to ensure accurate results. I would also increase the number of trials for this lab, in order to achieve more plentiful and accurate data.