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.
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
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: 1. Fill a beaker two-thirds full of water and add approximately 20 drops of IKI. Write down the solution's color and record the mass of the bag. 2. Do an initial Benedict's test on the 15% glucose/1% starch and the beaker solutions for glucose by putting some of the solution and a roughly equal amount of blue Benedict's solution in a test tube, placing the test tube in boiling water for 90 seconds, and observing whether or not the solution changes color from blue.
Materials and Methods Part 1 For the cation elimination test first 10 drops of potassium, iron (III), zinc (II), copper (II), and cobalt (II) were added to 5 centrifuge tubes and the color was recorded. Then for the metal hydroxide test, 6 M NaOH was added drop wise till a precipitate was formed. Each solution except potassium formed a precipitate, so then 10 additional drops of NaOH were added to the remaining solutions. Tubes were cleaned with distilled water and 6 M HCL. Next was the ammonia test 10 drops of each metal solution were added to new centrifuge tubes and 15 M NH4OH was added until the solution changed color or a precipitate was formed.
Sac #1 placed into beaker #1 with distilled water, sac #2 placed into beaker #2 with 40% glucose solution and so forth. 3. Before analyzing, we had to allow sacs to remain undisturbed in the beaker for 1 hour. 4. After 1 hour we boiled a beaker of water on the hot plate (for Benedict’s and AgNO3 test).
Dip the strip in the milk, Wait five seconds, Record Data 6. Now add a few drops of each acid or base to each cup 7. Dip a new glucose a strip and record your data 8. Add a few drops of enzyme to each cup 9. Use a new glucose strip and record Data: Conclusion: According to my data, pH levels do, in fact, affect the results of Lactex.
The liquid of homogenate was filtered into a beaker through Miracloth (2 layers cloth) to remove large plant components and 1 ml of the filtrate was transferred to a conical tube. 8.4 g of ammonium sulfate was slowly added to the 40 ml of the filtrate as it was stirred on a stir plate for 15 min to achieve 37% saturation (210g/L of solution). The solution was then centrifuged at a speed of 9000 x g at 4oC for 15 min to sediment the proteins. The resultant supernatant 1 was transferred to a beaker with 1 ml transferred to a conical tube and the obtained pellet 1 was resuspended in 4 ml of distilled water and transferred into a dialysis bag to remove the salt. 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).
Next, we put starch solution and a couple drops of iodine into a reaction tube, and recorded the color. We then got another reaction tube, put starch solution and saliva in it, and then put it underwater in a machine for 30 minutes. After the 30 minutes, we removed the tubes from the machine and added a couple drops of iodine to the solution. Lastly, we compared the colors of the two solutions to each other. Sweetness perception is the ability to taste sweetness.
Isolation of Caffeine Introduction Caffeine is a stimulant found in the cacao plant that is used, today to increase alertness when taken in moderate doses. In this lab, we extracted caffeine from 2 NoDoz tablets, which contains 45% caffeine. We accomplished this task by performing a hot gravity filtration to separate the insoluble binder from the caffeine, a liquid extraction to separate the organic caffeine-containing layer from the aqueous layer, a gravity filtration to filter off the hydrated salts, a steam bath evaporation to evaporate out the organic solvent, and a recrystallization to obtain dry caffeine crystals. The ultimate goal of this lab was to acquire the same amount of caffeine as listed on the NoDoz tablets. Materials and Methods Materials The compounds used in this lab are listed in the table below: Procedure We boiled 2 NoDoz tablets in grinded form with 60 mL of water in a 100 mL beaker and allowed it to cool to room temperature after it had been sitting on the hot plate for 5-10 minutes.