Mix well and let the solution stand for 5 minutes

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volumetric. Mix well and let the solution stand for 5 minutes. Fill the rest of the volumetric flask to the calibration line with DI water then mix using the same method as previously used. Using a spectrophotometer preset to the light wavelength of 508nm read the absorbance of the sample and the known solutions. Graph the results of all concentrations in order to find the concentration of the unknown sample. Prepare and standardize the solution of 0.02M potassium permanganate.to make combine 50mL of 0.1M KMnO 4 and 200mL deionized water to make a 250mL solution. To standardize
the solution titrate it with a solution of 0.05M oxalic acid (H 2 C 2 O 4 ). To get 0.05M oxalic acid combine 1.58 grams solid oxalic acid in 250mL deionized water and mix in a 250mL volumetric flask. Using a transfer pipette put 20mL 0.05M oxalic acid solution into an 250mL Erlenmeyer flask then mix with a solution of 15mL 3M sulfuric acid and 10mL deionized water. Heat to 80 o C and titrate while hot with potassium permanganate until the solution turns a very slight pink color. Dispose of in the proper waste container. Then repeat the process two more time to find standardize the concentration of potassium permanganate. Using the standardized KMnO 4 , repeat the process using 20mL of solution A in place of the 20mL of oxalic acid used in the first round of titrations. This solution although starting out as a highlighter yellowish green color will also turn the faint pink of the previous titrations. Repeat the titrations using solution A two more times to determine the standardized concentration in solution A. Observations In the first part of the experiment the original colors were a white solid and a clear liquid. Once 5 drops 3M H 2 SO 4 and 25mL of 1M oxalic acid (H 2 C 2 O 4 ) were added it turned a bright yellow color much like the Hofstra yellow. Once it was heated and precipitate started forming it turned a cloudy orange juice with pulp color. Once we dumped out the liquid from the yellow solid the discarded liquid was a light-yellow color lighter than the original yellow and clear not cloudy. The solid was not entirely solid as expected and was more of a sandy texture that wasn’t entirely able to separate from the discarded liquid. The next color change didn’t come until the adding of 10mL of saturated potassium oxalate (K 2 C 2 O 4 ). It changed to a bright orange color similar stereotypical prison jumpsuit color. The next change seen after the addition of hydrogen peroxide. it changed to a brown color like the color of pure coffee. Next color change was to an electric green with a slight precipitate forming on the bottom, fallowing the addition of ethyl alcohol. Once the crystals formed gathering all of the sample of the crystals proved slightly problematic but overall most of the sample was collected and far beyond the one gram needed.

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