Using a measuring cylinder, add 50cm3 of 1.0mol dm-3 sulphuric(VI) acid to the thyme extract in the conical flask. 8. Titrate the solution in the conical flask with the potassium manganate(VII) solution until a pale pink colour persists for 10 seconds. 9. Repeat the titration until there are two titres within 0.1cm3 of each other.
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.
SYNTHESIS 3 Purifying an unknown solid by recrystallization involved preparing cobalt amine chloride product. By adding five grams of cobalt II chloride into 20ml of 9M HBR in 250 mL beaker, plus 15 mL of deionized water. Dissolving the compound within pure water, filtration by gravity and adding two grams of activated charcoal and 25 mL of concentrated. Cooled after heating and additional six mL of 30 percent hydrogen peroxide. Filter by suction then collect the dark solid.
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.
Investigating the Chemical Composition of Alka Selzter Problem: How much sodium bicarbonate is in a tablet of Alka Seltzer? Purpose: To discover the amount of sodium bicarbonate, in grams, in a one tablet of Alka Seltzer. Materials: one Alka Seltzer tablet 50 mL of vinegar post-it note Triple beam balance beaker Procedure: 1) Put the post-it on the triple beam balance and zero the balance. 2) Measure the masses of the alka-seltzer tablet, and the beaker + vinegar. Record them.
The beaker was then moved to a stir plate with a stir bar and held in place by a ring stand. A funnel attached to an aspirator hose was fixed above to serve as a fume hood. With the aspirator and stir plate both on, 4.79 mL of 6 M HNO3 was added slowly to the beaker until the copper dissolved and the solution turned a light blue color. The hood could now be removed and 10.02 mL of distilled water was added to the solution. While stirring, 6 M NaOH was added drop-wise until the solution became basic, turning red litmus paper blue.
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.
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.
Examine the effect of heat on the solubility of albumin B. Examine the effect of pH changes on the solubility of albumin and casein C. Examine the effects of 95% ethanol, lead(II) nitrate, silver nitrate, and tannic acid on albumin and casein Procedure A. The effect of heat Place about 1 mL of 2% albumin in a test tube and heat it in a hot water bath for a few minutes. Compare the appearance to the albumin solution at room temperature. B.