A spin vane was added and a water-jacked condenser was attached. Isopentyl nitrite (0.06ml, 0.045 mmol) was dissolved in 1,2-dimethoxyethane (0.50 ml) in a 3-ml conical vial and caped to prevent loss by evaporation. Running the reaction. The mixture in the 5-ml conical vial containing the tetraphenylcyclopentadienone and anthranilic acid was heated on an aluminum block to 140° C. Once the mixture started to boil the prepared mixture of isopentyl nitrite was added to the 5-ml conical vial through the top of the condenser using a pasture pipette. The solution continued to boil for 25 more minutes until a
12. The TLC data obtained is provided in a table below. The TLC data was conducted solely in a 9:1 hexane/ethyl acetate solvent solution as opposed to the 1:1 and pure hexane solution as well. This was due to the lack of time, but as explained in number 7, a very polar solvent (1:1 solution) or non-polar solvent (pure hexane) is not ideal when obtaining
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
Apparatus- Chromatography column: C18 (10 microns particle size), with Guard column Flow rate: 1.2ml/min Pressure: 30-40kgf Wavelength: 326nm Mobile phase: methanol : water (95:5 v/v) Internal standard: retinyl acetate Injection volume: 20µl Procedure for Retinol extraction from serum samples- 1) 100 µl of serum sample and 100 µl of Retinyl acetate were added into 12 X 100mm glass test tubes. Vortex-mixed for 30 seconds. Then, kept them at 4 C for 5 mins. 2) 1mL of hexane was added and vortex-mixed intermittently for 60 sec. 3) Centrifuged at 2500 rpm for 12 mins.
Once cool to touch the squeeze out all the tea bags carefully without tearing them apart. Using a separatory funnel extract three times with 15.0ml of dichloromethane gently rocking bath and forth the funnel venting the funnel often each time. Carefully decant into a pre-weighed 125ml flask and add the drying agent-calcium chloride pellets- and the organic layer was evaporated off in a warm water bath. Using aluminum foil as support around the mouth of the flask place test tube in the flask and heat the flask on a hot plate whilst adding water into the tube without letting it boil. Once the caffeine forms crystals around the test tube scrape off all the sublimed product and weigh the dried product 0.1grams of caffeine and had a melting point range of 175-230
6) Next, prepare a 50 cm3 beaker, and pour both reactants into it. Wait for at least 1 minute to allow the reaction to reach completion. Procedure—Post-dilution 1) Use a pipette to fill 3/4 of each cuvette with the new solution from the beaker. Repeat until you have 4 cuvettes with the same solution. 2) Put a lid on each cuvette in order to prevent
When the Vitamin C tablet was dropped in the water, the reaction started and the solution kept fizzing for about 160 seconds. Following, the fizzing stopped meaning that the reaction has ended. However, when the powdered vitamin C was poured into the water, the solution stopped fizzing after about 132 seconds Average rate of reaction = Total volume of CO2 / Total time for the reaction Average rate of reaction (Whole Tablet) = 100 / 160 = 0,625 Average rate of reaction (Crushed Tablet) = 100 / 132 =
Reagents and solutions: Carrageenan: 0.5%–2.0% (w/v) carrageenan solution Pour 500 ml of sterile 0.9% saline into a 1-liter beaker and give a stir. Slowly add 2.5 g (0.5%) – 10.0 g (2.0%) carrageenan powder to the beaker. Heat the solution to 90°C with continuous stirring, do not allow the solution to boil. Heating the mixture helps to dissolve the carrageenan; it takes less than 1 hour to dissolve all of the powder. Pour the solution into a clean and sterile 1-liter glass bottle.
The concentration of starch of the 1ml solution from test tube A is 500 after dilute with 9ml distilled water in test tube A. The 500 of starch solution become more dilute after added into 9ml test tube B, which become 50 . The concentration of solution in the few next test tube decreases in such way. The dilution factor, 5000 ratio to 50 is 1 : 100 in test tube B while the dilution factor in test tube C, 5000 ratio to 5 is 1 : 1000 and so