In the first part, five 100 mL flasks of 5 mL ligand solution, 5 mL 2 M sodium acetate, 4 mL 3 M NH2OH, and 1-5 mL Fe2+ solution are diluted with water. The absorption spectrum for varying concentrations of Fe2+ are measured using a spectrophotometer and the data is graphed in Excel. The slope of the line is ε in the Beer-Lambart equation A = εcl. In the second part of the experiment, eleven flasks containing diluted stock solutions of Fe2+ and ligand are mixed with 5 mL 2 M sodium acetate and 4 mL 3 M NH2OH and diluted with water. The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel.
Record the mass of thyme used. 2. Using a measuring cylinder, add 50cm3 of 1.0mol dm-3 sulphuric(VI) acid and boil gently for 5 minutes. 3. Allow the mixture to cool for a few minutes then filter it, using either gravity or vacuum filtration.
Add 1 mL of deionized water to the small test tube containing the precipitate and mix it and centrifuge it for 60 seconds. Then, add the supernatant into the boiling test tube and repeat this step one more time with another 1 mL of deionized water. Acquire a pair of metal test tube holders and heat the boiling test tube to evaporate the water for 15 minutes. Let is cool after and weigh it. Then, calculate a percent yield of zinc iodide and write a balanced chemical equation and determine the limiting
Why is this necessary? Obtain an appropriate amount of 5.00 M NaCl and fill your 25 mL buret. Pipet a 20.00 mL aliquot of 0.100 M acetic acid solution into a 100 mL beaker, add a magnetic stirring bar, and then set up the titration apparatus as indicated in Figure 1. Record the initial pH and then begin titrating. You will titrate in 0.25 mL intervals for the first 2 ml and then in 1 mL intervals until a total of 6 mL of 5.00 M NaCl has been delivered.
The known nutrient solutions were used to create a base-line for protein, starch, and sugars. As listed in Table 1; protein (5g/L), Starch (0.2g/L), and sugar (20g/L) were separated in to 9 different test tubes at 2ml a piece, 3 per nutrient solution and tested for colormetry with the 400ug of the three reagents Lugol’s, Biuret, and Benedicts. Further steps were taken with the nutrients treated with Benedict’s reagent and they were heated in a water bath until they reached a constant 65 degrees C for 7 minutes and let cool to see color change. Distinguishing Organic Molecules in Unknown Dietary Supplements The same reagents used in setting the baseline were used to test the unknowns for nutrient content. Each of the 3 unknowns was distributed by dispensing 2ml of sample solution in to three test tubes.
Procedure Step 1, Obtain acid, in a 100 ml Erlenmeyer flask add 35 ml of .2M HCl solution. Step 2, add an indicator to the acid, select the flask and add 2 drops of phenolphthalein indicator. Step 3, Fill buret with NaOH, obtain a 50 ml buret and fill with .2M NaOH solution.Step 4, Titrate NaOH into HCl until end point, record initial buret volume and add NaOH (quickly at first then slowly) until the HCl solution turns pink and record the final buret volume of NaOH in buret. Step 5, repeat steps 1-4 using pH meters, add a pH meter to the acid solution. Record several points of pH and NaOH added (especially near equivalence point) to be use later to prepare a titration curve.
c. Prepare the solution by dissolving 38.90 grams of ZnI2 with 500 mL of water. d. 0.0125/0.25 = 0.05 L = 50 mL. This produces 0.0125 moles of ZnI2 5. Exercise 5: a. (0.125)(0.1) = 0.0125 moles of solute b. Pour 50 mL of the stock solution to get the number of moles needed.
Then, 3.4 g of ammonium sulfate was slowly added to the supernatant 1 as it was stirred for 15 min to achieve 50% saturation (85g/L of solution). The supernatant was then centrifuged at 9000 x g and 40C for 15 min and 5 ml of the second supernatant was transferred to a conical tube. The obtained second pellet was resuspended in 4 ml of distilled water and transferred into another dialysis
From the gel electrophoresis, we found that the PCR product was about 600 bps. Spectrometric analysis helped us to find the concentration of amplified DNA which was about 65 μL/mL. The next step was to produce digoxigenin-UTP labelled RNA probe by in vitro transcription of PCR amplified tau DNA with T7 RNA polymerase. About 4 μL of template DNA was added to a sterile, RNase-free reaction vial. The total sample volume was made up to 13 μL by adding water.
StudyBlue Flashcard Printing of Lab Final 2211L UGA http://www.studyblue.com/servlet/printFlashcardDeck?deckId=... In the distillation experiment, the purpose of a fractionating column was to Which liquid would be most easily separated from water by simple distillation? 1. 1-propanol (bp=97 degrees C) 2. 2-propanol (bp=82 degrees C) 3. tetrahydofuran (bp=65 degrees C) 4.