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.
After that, dissolve the sample in 2 mL of deionized water and shake the test tube for 1 to 1 ½ minutes to dissolve the solid. Place another dry test tube in a 50mL beaker and weigh it. Find a bottle of barium iodide and record the name and molar mass. Then, weight out either anhydrous barium iodide or barium iodide dehydrate into this test tube and dissolve is it in 2 mL of deionized water. Pour the contents of one of the test tubes into the other and a reaction should occur and you should see a white precipitate of barium sulfate form.
Nest two Styrofoam cups within one another 2. Turn on magnetic stirrer 3. Insert probe into cardboard lid 4. Pour 25mL of water into calorimeter 5. Determine initial temperature of water 6.
Obtain another 50-mL beaker and add 0.05g of Chromium(III) Nitrate to the beaker. Then, add 17 mL of distilled water and mix until the solid is dissolved. 3. Obtain a final 50-mL beaker and add 0.05 grams of the unknown substance to the beaker. Add 17 mL of distilled water and mix with a stir bar until the solid is completely dissolved.
Enough water should be added so that the flask is full to the 250 ml mark Tightly wrap the top of the flask with a Parafilm when finished 2. Set up the titration apparatus 3. Fill a dry 50 ml buret with EDTA solution using a small
Using another 125-mL flask, 60-mL of 0.3622 M potassium hydroxide in ethanol was deposited. Both flasks were clamped in a temperature-controlled bath regulated at 50.0˚C. The solutions were then set in the temperature bath for ten minutes to equilibrate. An empty 250-mL Erlenmeyer flask was also clamped in the same water bath. In another flask 50-mL of ice water was deposited with three-drop phenolphthalein.
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.
To the second, add 10% NaOH dropwise until the pH is 14. (To do this, add a couple of drops of NaOH to the tube; stir thoroughly with a stirring rod; then touch the stirring rod to a piece of pH paper to check your pH.) To the third, add 0.5% sodium bicarbonate solution to pH 9, and to the fourth, add 2% HCl to pH 2. Record your observations on the data sheet. Repeat the above tests using 2% casein solution.
Cylinder was rinsed with distilled water. * * 2. 2.0 ppm standard: 2.00 mL of 10.0 ppm phosphate solution was placed in a 25 mL graduated cylinder and diluted to exactly the 10 mL mark with distilled water then poured into a plastic cup labeled 2. Cylinder was rinsed with distilled water. * 3.
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.