Purpose Statement For Equilibrium

With these absorbance numbers a concentration curve was constructed and the unknown solution was determined by finding the point of absorbance on the curve.

10 microliters of the sample is then added and the assay absorption is measured at 340nm. If absorbance was above 1.5, samples were diluted.

The same solution of 0.5 ml BSA was then added from test tube 1 to the test tube 2 after being properly mixed, and from test tube 2 the solution was being added to test tube 3, and so forth all the way up to test tube 5, with the same exact procedure. From the last tube, we then disposed the 0.5 ml solution. After above procedures, we now labeled another test tube “blank”; 0.5 ml blank distilled water was purred into the tube with the serial dilution of 1:10. We also had a tube C labeled “unknown” with the same 0.5 ml of solution. And after adding 5ml of Coomassie Blue to each tube (1-5) and to the blank, the result of absorbance was read at 595 nm.

The objective of the experiment is to apply Le Chatelier's Principle, which is a system that responds to an external stress and then adjusts itself in order to alleviate the stress when it is at equilibrium. A reactant is added, and the equilibrium is reestablished, resulting in more products and fewer reactants, and thus, the position of equilibrium is shifted to the right. When a product is added, the equilibrium position is shifted to the left because there are more reactants and fewer products.

One of the most important skills to have in the chemistry lab is the understanding of how chemicals will react. Knowing for example, how a chemical will react with a metal, is an excellent way of determining the amount of a particular metal in a deposit. This knowledge was used in this lab to determine the amount of copper in an unknown sample mixture. It is also known that the determination of the percent concentration of a certain solution, will directly effect the percent transmission and absorption of a solution, dependent upon its dilution. By first testing known concentrations of a solution, and plotting this information graphically, a line is formed

A reaction has an equilibrium constant, Keq, of 50. When performed in the presence of an appropriate enzyme, the forward rate of reaction is increased 20-fold. What will happen to the reverse rate of reaction?

Part 1: Obtain some 0.200M Fe(NO3)3 solution and some 0.00020M KSCN solution. Starting from the first solution, pour and mix 8.0mL of Fe(NO3)3 solution and 2.0mL of KSCN solution into a test tube, where as the second solution has 7.0mL of Fe(NO3)3 solution and 3.0mL of KSCN solution. Continue this process until 5 test tubes have been filled. Pour

After the twenty minutes elapsed, the flask was cooled to room temperature and then titrated with the remaining NaOH until the colorless solution remained pink. The final volume was then recorded. While solution #1 was heating the same process was repeated with solution#2 and the second burette

10.Clean up: Rinse reaction vessel, empty collection box, dry table as needed, cleanup up any baking soda spills..

In this experiment, two reactions were run to determine the molar absorptivity and the equilibrium constant of FeSCN2+. The main principles used in this lab are equilibrium, LeChatlier’s Principle, Beer’s Law and Spectrocopy. The first reaction was run to completion using LeChatier’s Principle and the second reaction was run to equilibrium. A spectrophotometer was used to measure absorbances. Using a graph of absorbance versus concentration of FeSCN2+ was used to determine that the molar absorptivity constant was 3670. Beer’s Law was used to determine that the average equilibrium constant was 33.1793.

The absorbance is measured using a Plate reader and a Standard curve is generated. Also, the different types of pipetting techniques are assessed in this Assay.

Hibah Abbas Leonard-5/6 AP Chemistry 3/2/18 Le Chatelier’s Lab Write Up Chemical equilibrium is the state where the concentrations of all reactions and products remain constant over time. If a reaction takes place in a closed vessel, it will reach equilibrium. Le Chatelier’s

Incorporation of assay controls included setting up a spectrophotomer and running the chart recorder with a full-scale deflection before the start of the assay. The set recorder had a corresponding value of 1 for the change in the absorbance. Therefore, prior testing was done to observe whether a change occurred in the readings. This helped to indicate that the results were valid, as they could have been affected by a fault during the setting up of the spectrophotometer. On the other hand this was considered as one of the controls for the experiment. Nevertheless, a new cuvette had to be used for each assay.

LeChatelier’s Principle states that “if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change” (Clark, 2002). In simplified terms, in reactants are added, equilibrium shifts toward the products, and vice versa. In addition, if reactants are removed, equilibrium shifts to favor the reactants. The opposite of this scenario also holds true. In this experiment, LeChatelier’s Principle is used to maximize the product of the reaction between iron III ion and

The five solutions are then transferred into cuvettes and placed into a spectrophotometer, which is used to measure the absorbance of the five solutions in the UV range (535nm). The data obtained was then used to plot a graph in