Use the wash bottle with deionised water to transfer all the oxalic acid crystals from the glass beaker to the funnel. 11. Rinse out all the oxalic acid crystals with the wash bottle from the funnel in the volumetric flask. 12. Add deionized water to the volumetric flask to the 250ml mark on the volumetric flask.
pH, Percentage Drug Content and Content drug Uniformity Solution of 1g of gel dissolved in 30mL of distilled water was prepared and pH was determined by using digital pH meter (Systronics 361) and the results were summarized in the table 3. The drug Content Uniformity  was determined by the following method. 1g of gel was dissolved in a 100 mL of phosphate buffer pH 7.4 for 48 hrs with constant stirring using magnetic stirrer. Samples were taken from three different parts of the total ethosomal gel of 1g. Solution was then filtered and observed with UV-spectrophotometer at λmax 254nm.
First, 50 mL of the sample was placed into a 250 mL Erlenmeyer flask, and onto a stirring plate. Then, the pH of the solution was measured and adjusted to be within the range of 4 and 6, using nitric acid and sodium hydroxide. After the pH was optimal for the experiment, a single mL of indicator- acidifier reagent was added to the sample. Then, 50 mL of mercuric nitrate was place into a burette and titrated with the sample until the color of the solution turned from blue to purple. The volume of titrant used for the reaction to reach endpoint was recorded.
Abstract In this experiment, the reaction kinetics of the hydrolysis of t-butyl chloride, (CH3)3CCl, was studied. The experiment was to determine the rate constant of the reaction, as well as the effects of solvent composition on the rate of reaction. A 50/50 V/V isopropanol/water solvent mixture was prepared and 1cm3 of (CH3)3CCl was added. At specific instances, aliquots of the reaction mixture were withdrawn and quenched with acetone. In addition, phenolphthalein was added as an indicator.
The solution was then titrated with AgNO3 and volume used to generate the colour change was recorded. From the volume of AgNO3 used for the titration, the moles of Ag+ were calculated and found to be 0.005 moles of Ag+. Silver ions and iodine ions react in mole ratio of 1:1 to form the precipitate AgI (s). From the mole ratio it was calculated that 0.005 moles of I- reacted and thus 100% of I- was
We added sodium carbonate until the pH of the mixture was 8. After neutralize, we collected benzocaine by vacuum filtration. We used a Buchner funnel to collect benzocaine. We used three 10 ml of water to wash the product. After the product was dry, we weighed, calculate the percent yield and determined the melting point of the product.
Then the bank note was washed by either 20 ml Milli-Q water or 5 ml methanol. The bank note was dried and a second extraction was carried out to calculate the percent recovery. At the primary extraction, different concentration of methanol and PBS were examined. 100 %, 90%, 80%, 70%, 50% methanol: Milli-Q water and PBS were the solvent for extraction. The second extraction was mainly by 100 % methanol.
• Carefully decant the solvent solution from the drying agent through the funnel into the flask. Rinse the Erlenmeyer flask with about 10 ml of solvent and pour the solvent through the funnel, too. Remove the funnel, add two or three boiling chips and reattach the thermometer and adapter to the still pot. • Discard the magnesium sulfate remaining in the Erlenmeyer flask by dissolving it in tap water and pouring the solution down the drain. • Before beginning the distillation, weigh a clean, dry 1 narrow mouth screw cap bottle on a balance.