Read absorbance values for the timed phytoremediation solutions as follows. Reading the absorbance values, make sure you have waited 30 minutes to allow You will need to prepare a new blank standard: in a beaker, add 1 mL 0.5% cuprizone,ģ mL of pH 7.9 buffer, and 21 mL deionized water (carefully measure with aīetween sampling, set up the Spec 20 (600 nm), and calibrate with the blank Samples, dilute and mix as for the standards. Time permits, add 1 mL 0.5% cuprizone and 3 mL pH 7.9 phosphate buffer to the Prior to sampling, slosh the plant around to Placing each sample into clean, labeled 25 mL volumetric flasks. The volumetric pipet, remove 5 mL samples at 5, 10, 20, 30, 45, and 60 minutes, Let the water drain from its root mass, and noteĪnd place the water hyacinth into the bucket of Cu 2+ solution. Into a clean, labeled 25 mL volumetric flask. Properly rinse a 5 mL volumetric pipet and pipet 5 mL of this solution Of the Cu 2+ solution (10 ppm) - this is the contaminated wetland water sample. In the last decimal place, you should repeat the absorbance measurements for If either reading has changed by more than 5 Remove the cuvette and read transmittance. That the instrument is still properly blanked and zeroed, as follows: rinse inĪnd fill the cuvette again with the blank standard. Places in a data table in your lab notebook. Repeat for the remaining calibration solutions (leastĬoncentrated to most concentrated), recording absorbances to three decimal Stock solution, wipe off the outside, insert it into the instrument, and read Rinse in the cuvette with the solution prepared with 5 mL of Cu 2+ Store the run by choosing Store Latest Run from the Experiment menu in Logger Pro.
#LOGGER PRO ABSORBANCE FULL#
A full spectrum graph of the solution will be displayed. Fill the cuvette ¾ full with the solution and place it in the spectrophotometer.ī. To Determine the maximum wavelength ( l max Cu 2+ -cuprizone ~600nm) :Ī. NOTE: this blank standard will also be your first data point (zero concentration of Cu 2+ should give you zero absorbance). When the warm-up period is complete, select Finish Calibration. Place the blank in the spectrophotometer make sure to align the cuvette so that the clear sides are facing the light source of the spectrometer. Choose Calibrate from the Experiment menu of Logger ProĬ. Prepare a blank by filling an empty cuvette ¾ full with your blank standard.ī. Remove samples at the proper time intervals.Ī. ML volumetric pipet, and water, so that next week you will be able to rapidly You are waiting for the color to develop, practice with a pipet pump / bulb, a 5 Clean the flasks by rinsing once with 1M HCl, once with tap water, andįinally three rinses with distilled water. Of the solutions become colored at this stage, there is copper contamination
Measuring absorbance, allow the solutions to stand for 30 minutes or longer for In a beaker, prepare a blank standard of 1 mLĠ.5% cuprizone, 3 mL of pH 7.9 buffer, and 21 mL deionized water (carefully Carefully fill to the mark with deionized water, stopper and mix. Of pH 7.9 phosphate buffer to each flask. Solution into four clean, labeled 25 mL volumetric flasks.* Add 1 mL of 0.5% Cuprizone solution and 3 mL Dispense exactly 5, 10, 15, and 20 mL of this Rinse and fill a buret with the Cu 2+ stock solution (3.5 ppm CuSO 4). Remaining, and determine the efficiency of the water hyacinth in remediation. The polluted water in order to evaluate the Cu 2+ concentration At specific time intervals, samples will be removed from Will be exposed to a water hyacinth plant, which over time will absorb Cu 2+ concentration will be graphed in order to obtain a calibration curve.ĭuring the second week, a contaminated wetland water sample (polluted with Cu 2+) Solutions will be prepared at varying concentrations. Yellow copies of your lab work with your REPORT FORM. Of your work, data, and observations in your Laboratory Notebook. The BACKGROUND material, along with these procedures, before coming to lab.
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