Rate Reaction Of Crystal Violet
Melissa Carrithers
AP Chemistry
12/17/14
Rate Law Determination Pre-Lab
Purpose: The purpose of this lab is to observe the reaction between sodium hydroxide and crystal violet so that the order of the reaction could be determined along with the rate constant, k, and the half-life for this reaction.
Hypothesis: If the reaction between crystal violet and sodium hydroxide reacts appropriately, then the order will be first order.
Procedure: Mix 10 mL of sodium hydroxide and crystal violet solution together. After calibrating the colorimeter, insert the mixture. Absorbance data will be collected for three minutes. Analyze the data graphically to determine the reaction.
Discussion: The hypothesis that I stated was sadly, not supported by the data that my partner and I obtained. Comparing the regression of the two lines, the reciprocal of the concentration of the reaction (1/[A]), produced a straighter line by an approximate .0002. I thought that the natural log of the concentration of the reaction (ln[A]) would produce a straighter line due to past experiments and class examples. The most accurate way of producing the right results is through experimentation.
Conclusion: The purpose of the lab was to be able to determine the reaction order of the crystal violet solution through comparing graphs. Through experimentation, I found out that it is the most accurate way to come up with accurate results. Although our hypothesis was not correct, the lab did turn out well without error in the data and graph. During this lab, I was able to determine what the rate constant and half-life would be by determining the reaction order.
Post-Lab:
1. The reaction order of the solution was second order because the reciprocal of the concentration of the solution VS. time produced the straight line.
2. 1/[A] = [(k)(t) + 1]/[A^0]
6.3291 = k(30) – 5.4348
0.8943 = (30)k
K = 0.02981 1/M * sec 3. Rate Law: rate = k(CV+)^2 4. Absorbance at 0 seconds is 0.184. 5. Absorbance at 165
AP Chemistry
12/17/14
Rate Law Determination Pre-Lab
Purpose: The purpose of this lab is to observe the reaction between sodium hydroxide and crystal violet so that the order of the reaction could be determined along with the rate constant, k, and the half-life for this reaction.
Hypothesis: If the reaction between crystal violet and sodium hydroxide reacts appropriately, then the order will be first order.
Procedure: Mix 10 mL of sodium hydroxide and crystal violet solution together. After calibrating the colorimeter, insert the mixture. Absorbance data will be collected for three minutes. Analyze the data graphically to determine the reaction.
Discussion: The hypothesis that I stated was sadly, not supported by the data that my partner and I obtained. Comparing the regression of the two lines, the reciprocal of the concentration of the reaction (1/[A]), produced a straighter line by an approximate .0002. I thought that the natural log of the concentration of the reaction (ln[A]) would produce a straighter line due to past experiments and class examples. The most accurate way of producing the right results is through experimentation.
Conclusion: The purpose of the lab was to be able to determine the reaction order of the crystal violet solution through comparing graphs. Through experimentation, I found out that it is the most accurate way to come up with accurate results. Although our hypothesis was not correct, the lab did turn out well without error in the data and graph. During this lab, I was able to determine what the rate constant and half-life would be by determining the reaction order.
Post-Lab:
1. The reaction order of the solution was second order because the reciprocal of the concentration of the solution VS. time produced the straight line.
2. 1/[A] = [(k)(t) + 1]/[A^0]
6.3291 = k(30) – 5.4348
0.8943 = (30)k
K = 0.02981 1/M * sec 3. Rate Law: rate = k(CV+)^2 4. Absorbance at 0 seconds is 0.184. 5. Absorbance at 165