As mentioned in number 13, the data for the melting point makes sense because my pure product and given compound almost perfectly matched. 17. Again as explained in number 14, the TLC data made sense because my pure compound and 4-tert-butylbenzyl phenol had similar distances from the solvent origin of the plate. The presence of benzyl bromide and benzyl alcohol also explains how not all the product dissolved in the filtrate.
The polar silica gel in the column is the stationary phase and acts as an adsorbent, depending on the affinity of the component towards the stationary phase. In general, the more polar component would have a stronger interaction with the stationary phase, and the less polar component would be eluted out first. From the observations of the column chromatography, yellow S2 collected is β-carotene, indicating that
React ethanoic acid and 1-butanol under reflux with the presence of trace amount of concentrated sulfuric acid. In this step, the amount of 1-butanol and ethanoic acid used is the same so that a maximum 70% ester yield can be synthesised at the end of the experiment. After the reactants is accommodated in the reactant flask, the trace amount of concentrated sulfuric acid is added drops-by-drops into the reactant flask and the flask is swirled while adding the acid. Additional of concentrated sulfuric acid is to use as a catalyst to increase the rate of reaction by donating a proton to the oxygen atom in carboxylic acid to allow for the mechanism for esterification and thus, the satisfactory yield of ester can be achieved.
Introduction In a two-week laboratory experiment my group and I used the techniques of acid-base extraction and Thin Layer Chromatography (TLC) to extract the three active compounds in Excedrin- aspirin, acetaminophen, and caffeine- and confirm the identity of our extracted crystals. The purpose of this experiment is to introduce organic chemistry lab students to the laboratory techniques of acid-base extraction and TLC. This lab also offers the opportunity to apply the previously theoretical classroom concepts of acidity, solubility, and polarity in order to utilize acid-base extraction and TLC.
Kinetic investigation of TiO2 mediated photocatalytic degradation of Para nitrophenol Introduction In the manufacture of dyes, medicines and pesticides, nitrophenols are widely used as chemical intermediates. These are stable, carcinogenic and toxic. Para nitrophenol(PNP) is one of them and the presence of it in the environment is harmful for the living being.
Introduction Toluene, according to the International Union of Pure and Applied Chemistry system (IUPAC) – methylbenzene, is most commonly used to synthesize benzoic acid. The importance of benzoic acid in modern world is due to its uses: the acid and its salts are used as preservatives in food: benzoic acid is globally known as E210 and sodium benzoate as E211. The benzoic acid and its precursors are also used in pharmacy and hygiene products : the shampoo and shower gel that I am using all contain sodium benzoate. With its increasing production I was curious to explore the synthesis methods for benzoic acid and try it in the laboratory. Interestingly, in the U.S. the production of benzoic acid exceeds over 139 tons per year
In the stomach, food is thoroughly mixed with a digestive fluid, composed of hydrochloric acid, and other digestive enzymes to further decompose it. The buns protein, plus additionally protein such as cheese is mainly digested in the stomach.
The results do not support the hypothesis that a higher surface area to volume ratio would result in sulphuric acid being diffused into the agar cubes in the shortest amount of time. This is evident in the results as the exact opposite to what was predicted occurred. Instead of the smallest cube with the largest surface area to volume ratio of 1cm3 having the quickest diffusion rate, it conversely took the longest at 0.092 cm3 per second, whilst the 2cm3 cube with 0.0384 cm3 per second took the least amount of time. This directly refutes the hypothesis. There was also no consistent trend evident in the results.
The condensation product between the aromatic aldehydes and the aromatic ketones are 1,3-diphenylprop-2-en-1-ones, which are commonly known as chalcones. If any other types of aldehydes and ketones are used, the product is frequently known as α,β-unsaturated ketones. Chalcones and α,β-unsaturated ketones have been captivating, the medicinal, synthetic, and applied chemists by virtue of their structural units (Figure 1) which have been gained many access to tailor the molecule suitably for wide range of applications in medicinal, synthetic, and applied chemistry. The fluorine has the special topic of interest among the chemists as its introduction into the organic molecules leads to a dramatic changes in their physical and chemical properties. The recent activities show a remarkable growth in fluorine chemistry as the chemists practiced to do polishing the organic molecules with fluorine to improve their properties, leading to widespread applications in medicinal,[4b,c,5] agrochemicals,
Tetrachloroethylene is a clear, nonflammable liquid, and is a commonly used solvent that has been in commercial use since the early 1900s. It can be found in water repellant, paint remover, printing ink, glue, sealant, polish, and can also be used to make other chemicals. Although it has been detected in small amounts in the air and in some sources of drinking water, the most common source of exposure is in the industries that use this chemical. Such industries are the dry-cleaning business, where it is used as a solvent, and businesses that degrease and clean metals, or need to dissolve greases and oils from fabrics. Because Tetrachloroethylene is a chlorinated hydrocarbon, it is a central nervous system depressant, and can easily enter the body through respiratory or dermal exposure, allowing this to be taken into the body dangerously easy.
More specifically, this lab was met in terms of gaining an understanding in separating an acid, base and neutral compound from a mixture and identify through melting point. Overall, the experiment was successful as the acid (benzoic), base (5-chloro-2- methoxyaniline) and neutral (biphenyl) compounds were correctly identified. The separation of mixtures compounds to give pure components is of great importance in chemistry and in specific in organic chemistry. Many synthetic reactions give mixtures of products and it is important to isolate the wanted compound with a precise methodology of extraction and purification. Identification of the compound can always be identified by melting point