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Crystal Violet Formal Lab

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Crystal Violet Formal Lab
Determination of Reaction Rate Law from the Reaction of Crystal Violet with Sodium Hydroxide
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Abstract: This experiment helps determine the rate of reaction of crystal violet while it reacts with sodium hydroxide with respect to crystal violet. The amount of sodium hydroxide is varied in this experiment while crystal violet is kept at a constant. The transmittance of crystal violet is observed and recorded using a colorimeter and the data obtained is used to plot graphs which are manipulated using LoggerPro software to produce the desired outcome; rate of reaction of crystal violet. Upon completion of the experiment it was seen that the rate of reaction of crystal violet turned out to be 1 which meant the reaction was first order with respect to crystal violet. This was deduced upon plotting the graph of ln Absorbance versus time of crystal violet and by drawing the line of best fit, which showed that the slope graph was 1 which is the rate of reaction. This whole experiment was based upon the equation: Rate= k [CV+] [OH-], where k stands for the rate constant.
Introduction: Kinetics, which is the study of how fast a reaction takes place or in other words the rate of a reaction, is the main ideology in this experiment. Reaction rates can be measured in a number of ways: by monitoring the amount of product formed, by measuring the loss in mass of reactants, for reactions involving gaseous products measuring the volume of gas produced, by electrolytic conductivity, pH measurement or for colored reactants or products measuring the transmittance by the use of a colorimeter. In this experiment the last method of measurement is used which is colorimetry.
Colorimetry is a method of determining the kinetics of a reaction using a spectrometer which observes the amount of light that is absorbed or transmitted through a colored solution. As a reaction proceeds, the reactants either fades away or the product forms


References: 1. Atkins, P. W. (1978). Physical chemistry. San Francisco: W.H. Freeman. 2. Allen, J. P. (2008). Biophysical chemistry. Malden, MA: Blackwell Pub. 3. Lindon, J. C., Tranter, G. E., & Holmes, J. L. (2000). Encyclopedia of spectroscopy and spectrometry. San Diego: Academic Press. Appendix: Solution 1: Order 0, ǀRMSE/aǀ= 0.01641/0.271= 0.0605 Order 1, ǀRMSE/aǀ= 0.01129/0.271= 0.0416 Order 2, ǀRMSE/aǀ=0.3810/0.217= 1.4050 Solution 2, Order 1, ǀRMSE/aǀ=0.01566/0.134= 0.1169 Solution 3, Order 1, ǀRMSE/aǀ= 0.00693/0.492= 0.0141
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