By using the pseudo first-order kinetics method, you are able to determine the rate law for the reaction between crystal violet and hydroxide ion.
crystal violet hydroxide CV+ + OH- ————> CVOH Rate=k[CV+]m [OH-]n
The objective for this experiment was to analyze the absorbance of the dyed molecule crystal violet using a colorimeter and the molar absorbance of the reactant. This data was used to calculate the concentration of the the crystal violet and hydroxide ions. Using the integrated kinetics method, the rate law can be calculated for single reactant when converted to products, as well as the value of the rate constant, K, by the integrated rate law equations:
Zero Order: First Order: …show more content…
The reason we can use absorbance in place of concentration is because of Beer’s Law, which tell us that the absorbance of a solution is directly proportional to its concentration. For this specific experiment there are two reactants so the pseudo-first-oder kinetics method is needed. This can be accomplished by isolating the effects of the concentration of each reactant from the overall reaction rate. Therefore, by running the experiment with hydroxide in large excess, allowed us to view the effect of only the reactant Crystal Violet. By knowing the two different reaction orders for crystal violet and hydroxide, the rate constant “K” was able to be determined. After completing experiment one and two and plotting our data, the determined reaction order was first order for crystal violet and first order for hydroxide. Rate=k[CV+]1 [OH-]1. Understanding this method, can allow scientists to see important information of a reaction and can show beneficial things, like how effective creating a substance can be.
Discussion
This experiment used spectroscopic analysis of crystal violet to determine the rate
crystal violet hydroxide CV+ + OH- ————> CVOH Rate=k[CV+]m [OH-]n
The objective for this experiment was to analyze the absorbance of the dyed molecule crystal violet using a colorimeter and the molar absorbance of the reactant. This data was used to calculate the concentration of the the crystal violet and hydroxide ions. Using the integrated kinetics method, the rate law can be calculated for single reactant when converted to products, as well as the value of the rate constant, K, by the integrated rate law equations:
Zero Order: First Order: …show more content…
The reason we can use absorbance in place of concentration is because of Beer’s Law, which tell us that the absorbance of a solution is directly proportional to its concentration. For this specific experiment there are two reactants so the pseudo-first-oder kinetics method is needed. This can be accomplished by isolating the effects of the concentration of each reactant from the overall reaction rate. Therefore, by running the experiment with hydroxide in large excess, allowed us to view the effect of only the reactant Crystal Violet. By knowing the two different reaction orders for crystal violet and hydroxide, the rate constant “K” was able to be determined. After completing experiment one and two and plotting our data, the determined reaction order was first order for crystal violet and first order for hydroxide. Rate=k[CV+]1 [OH-]1. Understanding this method, can allow scientists to see important information of a reaction and can show beneficial things, like how effective creating a substance can be.
Discussion
This experiment used spectroscopic analysis of crystal violet to determine the rate