Lab Report On Chromatography

The purpose of this experiment is to determine the maximum absorbance of fast green, and the chlorophylls, also in the case of fast green create a concentration curve to determine an unknown substance. Each test will use the spectrophotometer.

The mole is a convenient unit for analyzing chemical reactions. Avogadro’s number is equal to the mole. The mass of a mole of any compound or element is the mass in grams that corresponds to the molecular formula, also known as the atomic mass. In this experiment, you will observe the reaction of iron nails with a solution of copper (II) chloride and determine the number of moles involved in the reaction. You will determine the number of moles of copper produced in the reaction of iron and copper (II) chloride, determine the number of moles of iron used up in the reaction of iron and copper (II) chloride, determine the ratio of moles of iron to moles of copper, and determine the number of atoms and formula units involved in

Time) because it had a correlation closest to 1. All three orders were graphed and a linear regression was used to see which graphed order was closest to 1. The order was determined by comparing the concentration and time to the mathematical predictions made using the integrated rate laws. Analyzing each graph and finding each correlation helped determine which graph was closest to 1. The more concentrated a solution is, the higher the absorbance of that solution. This is due to Beer’s Law. The law measures the absorbance of a solution by determining how much light passes through a solution. As the concentration of a solution increases, fewer wavelengths of light are able to pass through the concentrated solution. The absorbance at 60 seconds was 0.573 (Figure 1: Table1). To calculate the concentration (molarity), the Beer’s Law equation was used, Abs = slope(m)+b. Plugging in what is known into the Beer’s Law equation resulted in 0.573 = 3.172e+004 + 0, where the concentration is determined by M = 0.573-0/ 3.172e+004. So, the concentration at 60 seconds using the equation (M = 0.573-0 / 3.172e+004) was 1.824e-5 M. The 1st order graph resulted in k=0.006152 (Figure 1: Graph 1). Other groups also resulted in their decolorization of CV to be the 1st rate

b) Enter “1/absorbance” as the long name, “1/abs” as the short name and leave the unit blank. Then click on the definition tab.

The dark, navy blue colored graph represented the absorbance curve for the S1 sample. The red colored graph represented the absorbance curve for the S2 sample. The green colored graph represented the absorbance curve for the P1 sample. The purple colored graph represented the absorbance curve for the P2 sample. The gaps between the P2 curve was due to the oversaturation that led to the inconclusive spectrophotometer readings. The blue colored graph represented the absorbance curve for the P1 low salt sample. The orange colored graph represented the absorbance curve for the P2 low salt sample. The light blue colored graph represented the absorbance curve for the P1 medium salt sample. The light pink colored graph represented the absorbance curve for the P2 medium salt sample. The light green colored graph represented the absorbance curve for the P1 high salt sample. The light purple colored graph represented the absorbance curve for the P2 high salt

The values of color absorbance are effective because color absorbance has a linear relationship with concentration values, which in turn, allows us to easily find concentration values for many solutions. Beer’s law describes this phenomenon since the absorbance is directly proportional to concentration. We observed that as the color absorbance increased, the concentration of the FeSCN2+ complex ion increased. This is because as the FeSCN2+ concentration increases, the blood-red color becomes darker due to more presence of the blood-red FeSCN2+ ion. Therefore, the color absorbance increases because there is more blue color absorbed by the darker red color. We then graphed the absorbance and concentration values and created a line of best fit. Using the line of best fit, we were able to predict the equilibrium concentrations of the FeSCN2+ solutions and find the change required to reach equilibrium. Since we already knew the initial concentration of FeSCN2+ and since we already found the equilibrium concentration of FeSCN2+, we can calculate the change in equilibrium. Using this data, we were able to calculate the equilibrium concentration of all of the species in this lab, since we already knew the change from the initial concentration to the equilibrium change. Q is less than K because there was no initial concentration of FeSCN2+, but after the system reached

14. Different levels of brightness are due to different levels of heat, and different distances.

Figure 1. Results recorded from experiment. After every 15 seconds for four minutes, the absorbance was recorded.

Photosynthesis is a food making process for algae and plants. The photosynthesis process rate varies from different wavelengths and intensities of light. This lab will evaluate the optimal wavelengths and degrees of intensity during photosynthesis when chloroplast is exposed to light. The mixtures of DCPIP with water, PO4 buffer, and chloroplast will be prepared in a number of cuvettes. The cuvettes were tested individually at different wavelengths and intensities to find the optimal rate of photosynthesis by using a spectrophotometer, measuring the greatest change in absorbance. From this experiment, two data charts and four graphs were obtained. The hypothesis was set from graphs obtained in this lab, and the optimal reaction

Each solution contained different concentrations as follows: 0.005 mg/mL, 0.010 mg/mL, 0.015 mg/mL, 0.020 mg/mL, and 0.025 mg/mL. Each solution needed to have a volume of 10 mL. Before adding the different concentrations of Coomassie Blue into their separate tubes, the formula C1V1= C2V2 was used in order to determine how much stock solution is needed for the five dilute solutions. Once that number was calculated, a pipette was used to add the amount of stock solution needed for each tube. We then subtracted the amount of stock solution from 10 mL to determine the amount of H2O needed. The calculated amount of H2O was then added to each tube of solution. After doing that, a spectrophotometer was used to determine each solution’s relative absorbance. However, before that, we first had to calibrate the spectrophotometer before determining each solution’s relative absorbance. In order to calibrate the spectrophotometer, a disposable culture tube filled with distilled water was used. We then changed the data rate to 100 and removed the tube with water. In order to determine the relative absorbance, the relative absorbance had to be at 595 nm. Also, during this experiment, an unknown dilution was given to us by the lab instructor. We determined the relative absorbance by using the spectrophotometer and then recorded the results. The procedures for this experiment can be found on page 8 of

Solute concentrations affect the rate of diffusion, so I expect the 1% solution to diffuse slower and the 10% solution to diffuse faster. The 10% solution would be expected to diffuse at a greater rate, maybe twice that that of the 5% solution, so the plotted line will be significantly above the 5% line. The 1% solution will have a line plotted at significantly lower values than that of the 5% solution. The 0% solution will remain at a value of zero, a flat horizontal line, as no diffusion is expected to occur.

With the slope we get from the graph, we calculated the different PNP concentrations versus the absorbance at 410 nm to then have the results for the extinction coefficient. Which gave a final answer of 18.2 mM-1cm-1

Dispense .5 mL water into the already weighed conical vial, replace cap and face insert on its down side.

concentration, record the absorbance readings at a fixed wavelength, and plot the absorbance vs. concentration data. The wavelength of 520 nm was selected for experiment Part

Chromatography Investigation Chromatography is a highly regarded technique used to separate the components of a mixture. It is based on the principle that each component possesses a unique affinity for a stationary phase and a mobile phase. The components that are more inclined to enter the mobile phase will migrate further on the chromatogram and distinguish themselves from the other components. The type of solvent used in chromatography is known to directly affect the separation of the mixture. In this experiment, thin-layer and column chromatography will be utilized to separate the numerous chlorophyll and carotenoid pigments of a spinach extract.