spots corresponding phospholipids may be carbonized by the addition of phosphomolybdic acid, sulfuric acid or copper sulfate in phosphoric acid, and then heating of the sample. The result charred spots can be scraped off the plate and measured by densitometry. In order to visualize the spots without charring, solutions such as rhodamine 6G or berberine can be used for UV-detection. iodine vapor is commonly used; but it does not work well with lipids which do not contain double bonds (Hoving,
Experiment 2 Report Scaffold (Substitution Reactions, Purification, and Identification) Purpose/Introduction 1. A Sn2 reaction was conducted; this involved benzyl bromide, sodium hydroxide, an unknown compound and ethanol through reflux technique, mel-temp recordings, recrystallization, and analysis of TLC plates. 2. There was one unknown compound in the reaction that was later discovered after a series of techniques described above. 3.
It is to prevent the cell from washing away during the staining and washing process. Then, it is air dried and followed by fixing it with flame from Bunsen burner. After fixing the smear, it must be stained using Gram staining solution, firstly crystal violet solution was flood onto it, and allowed for 1 minute, then wash off with tap water. Then, flood the slide with iodine solution for 1 minute and wash it off with tap water again. The formation of a dye-iodine complex will occur in the cytoplasm.
This mixture was poured into the burette with the stopcock closed. The resin that had stuck to the sides of the burette was washed down by pipetting extra pH 3 citrate buffer along the sides. The column was tapped to ensure that the settled resin formed a level surface. After all of the resin settled, the buffer was drained into a waster beaker until the level of the buffer reached the top surface of the resin. For the remainder of the experiment, the top surface of the resin was not allowed to dry
NOTE: Record the grams of gasoline, kerosene, and lubricating oils that are present in the 50 mL of crude oil. ➢ Select the flask, and choose Heating Mantel option afterward select Max Heat and make sure you record the temperature when you see crude oil begins to boil. ➢ When the crude oil begins to boil, Make sure you turn the temperature down to 60% by decreasing the heating metal two times. Step 3: Record the
Acid-Base Extraction and The Extraction of Caffeine from Tea Bags and Purification by Sublimation. Summary: The isolation of organic compounds in a solution can be performed due to the difference in solubility in different liquids. The extraction of the benzoic acid ,3-nitroaniline and 9-flourene mixtures by adding different amounts of solvents and extracting the acidic, basic and the organic solvents the purity of the samples were then determined by comparing them to the literature value of the melting point. The percent recovery for the benzoic acid was 81.1%, the 3-nitroaniline was 52.9% and the organic extract was 158.8% this was cause by a large number of impurities that had occurred whilst conducting the experiment. The benzoic acid was found in the acidic extract while the 3-nitroaniline was found in the basic extract and the organic extracted contained the 9-flourene, this was determined by the comparison of the melting point range to the actual value.
In this experiment, extraction was used as a separation technique to separate the acid, base, and neutral compounds. In extraction, two immiscible solvents with opposite polarities are used to dissolve different parts of the solute with different polarities, so they form two distinct liquid layers. In this experiment, methanol, an organic solvent, and an aqueous solution were used as the two immiscible solvents. The extraction solvent must also be capable of dissolving one of the mixture components. While initially it seems as though methanol, an organic solvent would be incapable of dissolving a polar acid or base, the conjugate of the acidic and basic compound will dissolve in methanol.
It helps to prevent strokes, heart attacks and blood clot formation. It can be produced from salicylic acid and acetic anhydride, with acetic acid as its by-product. However, salicylic acid consists of the phenolic and carboxylic acid groups which are way too acidic for the stomach lining. Thus, acetylsalicylic acid (aspirin) was refined to become a more effective substitute. Theories In this experiment set-up, acetic anhydride is added to salicylic acid in the presence of a catalyst, concentrated sulphuric acid.
Introduction: Titration process is used in an acid-base experiment in order to determine the concentrations of solutions of acids and bases. Through the titration process, we are able to identify physical changes to the mixture such as the colour change to indicate the end point of the experiment. For example, the colour changes of phenolphthalein from colourless to pink and methyl orange from red to orange and subsequently yellow. Acids produce hydrogen ions and bases produce hydroxide ions. This causes the indicator to change colour due to the colour difference from the undissociate molecules.
The two solvents were added to the funnel, and the funnel was capped and the stopcock was closed to avoid spilling of solution. The funnel was then turned over several times for several minutes to let the aqueous and organic layer make contact by increasing surface area of reaction. The stopcock was periodically opened to relieve the air pressure that built up due to gaseous products formed by the reactions. In the first step, HCl was added to the ethyl acetate, which protonated the organic base, forming the base’s conjugate acid, which was polar and hence soluble in the aqueous solution. The aqueous layer was drained, and NaOH was added to neutralize the solution, and deprotonate the conjugate acid to reform the original base, which, as an organic base, was mostly insoluble in an aqueous solution, and precipitated out.