Determination Of Equilibrium Constants
Determination of Equilibrium Constants
Introduction Bromothymol blue is an indicator for many acid-base titrations. When adding different solutions within the indicator it is to react and change colors, in this experiment the different colors were blue, green, and yellow. In the following experiment, obtaining the absorbance levels for each one makes it possible to calculate the equilibrium constant.
Materials and Methods For this specific experiment there are a few materials that are crucial to finish the experiment. First and foremost a Spectrophotometer will be necessary to measure several wavelengths. The specific spectrophotometer that will be used is the Spectrovis-Plus. In order to measure the different solutions, the solutions are held in 1.0-cm path-length cuvettes. To prepare the different solutions they are to be in four different 50mL beakers, one 150mL beaker, and a larger 250mL beaker for waste. Obtaining each different solution was through three different burets. Last but not least, pipets were needed to transfer solutions; this calls for a 5.0mL pipet and an optional disposable pipet. Collect 50mL of pH buffer solution the pour it into the 150mL beaker. The pH of the buffer solution was 6.83. After pouring the pH solution into the 150mL beaker, add 20 drops of bromothymol blue solution. Using a pipet agitation of the solution can be helpful to see the color change. The color change after adding these two solutions, the new solution should be green. Make sure the 5mL pipet is contaminated from previous class experiments; rinse the pipet out with the buffer solution. Next measure 5.00mL of the green-buffered solution and add to each 50mL beaker. Make sure that the small beakers are clean and dried thoroughly. After adding the solutions into each beaker, add and label 1.0 M HCl, 1.0 M NaOH, and 1.0 of water. Labeling of the colors is not necessary because it is obvious of what each beaker color change is present. Reaching for the cuvettes, dry
Introduction Bromothymol blue is an indicator for many acid-base titrations. When adding different solutions within the indicator it is to react and change colors, in this experiment the different colors were blue, green, and yellow. In the following experiment, obtaining the absorbance levels for each one makes it possible to calculate the equilibrium constant.
Materials and Methods For this specific experiment there are a few materials that are crucial to finish the experiment. First and foremost a Spectrophotometer will be necessary to measure several wavelengths. The specific spectrophotometer that will be used is the Spectrovis-Plus. In order to measure the different solutions, the solutions are held in 1.0-cm path-length cuvettes. To prepare the different solutions they are to be in four different 50mL beakers, one 150mL beaker, and a larger 250mL beaker for waste. Obtaining each different solution was through three different burets. Last but not least, pipets were needed to transfer solutions; this calls for a 5.0mL pipet and an optional disposable pipet. Collect 50mL of pH buffer solution the pour it into the 150mL beaker. The pH of the buffer solution was 6.83. After pouring the pH solution into the 150mL beaker, add 20 drops of bromothymol blue solution. Using a pipet agitation of the solution can be helpful to see the color change. The color change after adding these two solutions, the new solution should be green. Make sure the 5mL pipet is contaminated from previous class experiments; rinse the pipet out with the buffer solution. Next measure 5.00mL of the green-buffered solution and add to each 50mL beaker. Make sure that the small beakers are clean and dried thoroughly. After adding the solutions into each beaker, add and label 1.0 M HCl, 1.0 M NaOH, and 1.0 of water. Labeling of the colors is not necessary because it is obvious of what each beaker color change is present. Reaching for the cuvettes, dry