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.
The concentrated extract was then passed through a chromatographic column (30 cm x 10 mm i.d) containing 2 g florisil (lower) and 1 g sodium sulphate (upper) which is pre wetted with hexane: acetone (1:1). OCPs were eluted with 25 ml hexane: acetone (1:1).The solvent was evaporated using rotary evaporator and final volume was adjusted to 5 ml, which is used for GC analysis. All the sediments were analyzed for HCH and
3) Centrifuged at 2500 rpm for 12 mins. Upper hexane layer (supernatant) was transferred carefully into another test tube. 4) Evaporated the hexane under a stream of grade 1 nitrogen gas and added 100 µl of methanol to the residue left and vortexed for 1 min. 5) Injected 100 µl of extract in HPLC vials and closed properly. Standard curves and calculations- Retinol was quantified from standard curves peak area for each vitamin.
Dissolve the salt in 60 ml of tap water. Add 30 ml 6 M Hcl and stir the mixture with a glass rod. Add 12 g solid Nacl to the solution and stir the mixture for about 2 minutes. Support a 250 ml separatory funnel on a ring, making sure that the stopcock is closed and that a clean beaker is placed beneath the exit tube. Transfer the aqueous solution from the beaker to the separatory funnel.
3- Add 0.05 moles of concentrated sulphuric acid to round bottom flask very slowly and carefully then put a magnetic stirrer . 4- Set up reflux system using a clean and dry condenser .
The incubation mixture contained 2.5 ml of 1.2% (w/v) fibrin, 2.5 ml of 100 mM Tris–HCl buffer, 10 mM CaCl2 (pH 7.8), and 20 µg of enzyme. The incubation was carried out at 37°C for 30 min, and the reaction was stopped by adding 5 ml of 110 mM trichloroacetic acid containing 220 mM sodium acetate and 330 mM acetic acid. This reaction mixture was centrifuged at 3,000×g for 5 min, and the absorbance of the trichloroacetic acid (50 mM) soluble product was determined at 275 nm. One unit of fibrinolytic enzyme activity was defined as the amount of enzyme required to liberate 1 µg of L-tyrosine per minute at 37°C. The total protein determination was performed as described by Lowry et al.
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.
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.
One millilitreer of the lichen extract (1 mg/mL) in a volumetric flask was diluted with distilled water (46 mL), and the content was mixed in a volumetric flask after adding. oOne millilitreer of Folin-Ciocalteu reagent was added and the content of the flask was mixed. thoroughly . After 3 min, 3 mL of 2% sodium carbonate (2 %) was added and then was allowed to standleft for 2 h with intermittent shaking. The reaction absorbance of prepared mixture absorbance was measured at 760 nm in a spectrophotometer (Jenway UK).
Using the thermometer, the temperature was measured and recorded. Then, the 25-mL graduated cylinder was filled with 25 mL of distilled water, and its mass was measured and recorded. The density of the water was found using the temperature and the Density of water index. Moreover, the calculated volume of water was calculated using the formula of density, and the difference between observed volume and calculated volume was found. This process was then repeated using the 50-mL beaker and the results were recorded.
50 μL of these dilution solutions were separated on the TLC plate coated with SNISG. The plate was developed with petroleum ether: ethyl acetate (4:1) and the movement of solvent was usually controlled at 1 cm from the upper edge. After completion, the plate was dried until no solvent smell remained. It was sprayed with an ethanol solution containing 10% sulfuric acid, and heated at an infra-red drier until obvious color came up, as shown in Fig.2 (B.ab). Simultaneously, the amount of silver nitrate in the impact of isolative effect was investigated with the sample procedure, as shown in Fig.2
1. 150 ml of boiled water was poured into each of the three beakers labeled A, B, C. 2. Five tea bags were soaked for the time given by the manufacturer (two minutes) , in beaker A (Control). The teabags were immediately removed after the time elapsed. 3.
Experiment 13.1 Purpose: To determine the ∆H of a chemical reaction. Materials: 2 Styrofoam cups, Thermometer, Vinegar, Mass Scale, Measuring tablespoon and ½ teaspoon, Lye, and Safety goggles.
The purpose of this experiment was to learn about metal hydride reduction reactions. Therefore, the sodium borohydride reduction of the ketone, 9-fluorenone was performed to yield the secondary alcohol, 9-fluorenol. Reduction of an organic molecule usually corresponds to decreasing its oxygen content or increasing its hydrogen content. In order to achieve such a chemical change, sodium borohydride (NaBH4) is used as a reducing agent. There are other metal hydrides used in the reduction of carbonyl groups such as lithium aluminum hydride (LiAlH4).