You may find information in reference books, in libraries, in pharmacies and by contacting pharmaceutical companies, or the abpi association of the british pharmaceutical industry, 12 whitehall, london sw1a 2dy, tel 020 7930 3477. This bibliography was generated on cite this for me on sunday, may 3, 2015. Results page 4 about sample apa synthesis free essays. Pubchem contains various types of records, but in all cases they can be found with the data type and record identifier in the records url. Look up the melting points of salicylic acid and aspirin acetylsalicylic acid in a reference book or online. The first part of the experiment aims to synthesize aspirin from the reaction of salicylic acid with acetic anhydride. Mashkovskys manual, a standard reference book on pharmaceuticals for medical practitioners in the former soviet union, lists about 50 synonyms of aspirin with the following footnote. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more. Experimental planthe reactants salicylic acid and acetic anhydride will be reacted together using the method and experimental technique outlined below. Synopsisthe objective of this experiment is to learn to recrystallise aspirin and to prepare aspirin.
However, formatting rules can vary widely between applications and fields of interest or study. Aspirin is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antiinflammatory compound that inhibits cox1. These are the sources and citations used to research synthesis of aspirin. To find out the purity of aspirin obtain by recrystallisation of prepared aspirin from reaction of salicylic acid with acetic anhydride. Melting point is a useful measure for the purity of a solid. Reviewing over a century of aspirin research and use, aspirin and related drugs provides a comprehensive source of information on the history, chemistry, absorption in the body, therapeutic effects, toxicology, elimination, and future uses of aspirin. As both types of aspirin melted over a temperature range of 5c its indicative that both substances have many impurities. Mar 23, 2017 if youre writing a lab report for a science class and find that you need to quote or paraphrase information from another source, its important to cite the source properly. The sharpness of the melting point is useful to measure purity using pure aspirin as a comparison.
Earlier this semester you synthesized aspirin from salicylic acid. Aspirin is only found in individuals who have consumed this drug. Hence, the depression of the melting point of individual crystals is related to the. Preparation of aspirin experiment 5 introduction in this experiment you will prepare a sample of aspirin, recrystallize the raw product, and determine the percentage yield of the aspirin based on the limiting reactant. Results page 3 about sample apa synthesis free essays. At the end of the experiment, the result gotten should be a result of 40 60 % yield and a melting point that is around the theoretical melting point of aspirin, which is 5ac 6ac. Melting point tips and guidelinesif the melting point of a pure compound is within a degree of the value found a lab a sample is impure if it has a melting point range that is lower andor wider than below finally at a temperature of 75, all of the solid has aspirin ourmedin the course of his work on the synthesis and properties of. The purity of the synthesized aspirin was measured by determining its melting point and percent yield. Synthesis of aspirin and determination of melting point a. The experimental melting point range of aspirin was determined to be 122 2c.
Nine years later however, the uspstf issued a grade b recommendation for the use of lowdose aspirin 75 to 100 mgday. Determining the relative percent yield and attained purities of different synthesis processes is vital to the viability of an affordable commercial product for the aspirin. Unlike previous reactions where you assumed a 100% yield, this was an equilibrium reaction which resulted in less than 100% yield. If impurities are present in your crude sample, the melting point range for your product will be lower than the range of pure aspirin. Please use the record url or identifier to locate and reference it. Clicking on the donut icon will load a page at with additional details about the. Acetylsalicylic acid was recrystallized from ethanol in a crystallizer which. The recrystallization and dissolution of acetylsalicylic acid ubc. The altmetric attention score is a quantitative measure of the attention that a research article has received online.
The important thing to remember is that a pure compound will have a small, 1c to 3c range. This experiment also enables students to conduct the synthesis of aspirin, reinforce the skills of recrystallisation and also the technique of melting point. Preparation and recrystallisation of aspirin writework. According to the melting point values the aspirin product. The problem with getting a value for the melting point of an organic substance is the purity of the material.
These are the sources and citations used to research asprin. Determination of the melting point most organic compounds have a sharp melting point, which can be measured accurately to within 1oc or better, using the method below. May 20, 2010 after recrystallizing aspirin and drying the crystals 2 days, i ran a melting point on the sample and obtained a range of 2. Aspirin synthesis lab report by eddie zhang on prezi. The melting point range of pure aspirin is 8140 c and the melting point range of the salicylic acid starting material is 158161 c. Normally an impure compound will show a melting point which is lower than that of a pure compound. Determining the relative percent yield and attained purities of different synthesis processes is vital to the viability of an affordable commercial product for the aspirin market. How to cite references in a lab report pen and the pad. Our recrystalized aspirin product had a melting point range of 110. The average values of the melting points obtained by the laboratories can therefore be used as constants for the substances in question, which have accordingly been established as who melting point reference substances and included in the who collection of authentic chemical substances. Results at the end of the experiment, the result gotten should be a result of 40 60 % yield and a melting point that is around the theoretical melting point of aspirin, which is 5ac 6ac.
Pure aspirin has a narrow temperature range during which it changes from a solid to a liquid. Soluble impurities increase the range over which a compound melts and often decreases its overall melting point temperature1. We can see that the difference in the melting point is getting less as the number of recrystallisation increase and closer to the melting point of aspirin published in the data booklet. The value for our melting point was found to be 2oc. Preparation of aspirin and determination of the melting point ferrer, lara melissa v. Nist chemistry webbook the national institute of standards and technology nist uses its best efforts to deliver a high quality copy of the database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. One use of the melting point is to establish that a preparative or isolation procedure has led. This question hasnt been answered yet ask an expert. The synthesis of aspirin is actually an esterification reaction. The melting point temperature ranges were 126oc2oc and 129oc4oc for the crude and recrystallized aspirin samples, respectively.
Due to its wide range, and lower value than that of the theoretical melting point of 6c, it was assessed that the prepared aspirin was impure. Therefore, if the sample of aspirin melts at a temperature below the accepted melting point two possibilities can exist. Range of the melting point indicate the purity of the compound. The search on this page works by searching the content of each page individually, much like any web search. We offer publicly available, official documentary standards for pharmaceutical ingredients in the usp nf that link directly with a primary reference standard.
C, which is slightly lower than the literature range for aspirin of 46. Salycilic acid has a higher melting point than the ester as the crystal lattice forms stronger bonds between the molecules, and so needs more heat or energy to melt it. Because melting point is a unique physical characteristic of a substance, melting point analysis does have high specificity. The melting point of acetylsalicylic acid carswell. Look up the melting points of salicylic acid and aspirin acetylsalicylic acid in a reference book or online and compare with the melting point of the reaction product. Usp reference standards are rigorously tested and evaluated by multiple independent commercial, regulatory, and academic laboratories to confirm accuracy and reproducibility. Acetylsalicylic acid, european pharmacopoeia ep reference standard acetylsalicylic acid. Aspirin or acetylsalicylic acid acetosal is a drug in the family of salicylates, often used as an analgesic against minor pains and aches, antipyretic against fever, and antiinflammatory. These are the sources and citations used to research aspirin and paracetamol. Once it is a liquid, the boiling point is the temperature that the vapor pressure of the liquid is large enough that bubbles form inside the body of the liquid. In cold water aspirin is insoluble but as the water heats up the solute starts to dissolve. Why does salicylic acid have a higher melting point than aspirin. Use the link below to share a fulltext version of this article with your friends and colleagues.
The amount of each compound should be the same because there is a 1. The concentration ratio of aspirin semenplasma was 0. A small amount of sulphuric acid will also be used. Acetaminophen paracetamol is a selective cyclooxygenase2 inhibitortarget. The narrow range of melting seems to indicate that the sample is pure, but the slightly depressed melting point doesnt support that. Using recrystallisation improve the purity of aspirin biology. Further evidence to my theory that the number of recrystallisations increases the purity is my melting point data. Chemistry 51 experiment 11 synthesis and analysis of aspirin. Wi th refe rence to scientific litera tures, the melting point of pure aspirin is expected to be 8c to 140c. Melting point apparatus is commonly used for this purpose. By acid derivative, salicylic acid is treated with acetic anhydride, which will giving a chemical. If the experiment went as expected, a pure sample of aspirin with a high percent yield would have been obtained. Salicylic acid has a melting point range of 158161oc which is significantly higher than pure aspirin which melts at 5oc. Oct 24, 2011 the actual melting point is given as 5c but the compound will decompose at around its boiling point of 140c.
The melting point of a compound can be used to identify it and also to estimate its purity. Highlighting the historical evolution of the salicylates and the commercial development of. The name penicillin can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Pure aspirin has a melting point in the range of 51400c. Using thinlayer chromatography to investigate aspirin 7. It is a derivative of salicylic acid which is also an. Using recrystallisation improve the purity of aspirin. Melting points, boiling points, and refractive indices distillation steam distillation vacuum distillation and sublimation. I predict that the melting point high range is due to the fact that multiple compounds. Experimental synthesis of aspirin and melting point purity.
Clicking on the donut icon will load a page at with additional details about the score and the social media presence for the given article. And in general, what should i do when i encounter contradicting chemical data. The first part of the experiment aims to synthesize aspirin from the reaction of salicylic acid with acetic anhydride with the aid of phosphoric acid as a catalyst. The mean peak concentration of salicylate in plasma was 49 microgramsml range, 4262 microgramsml, reached in 2. Aspirin, an acetyl derivative of salicylic acid, is a white, crystalline, weakly acidic substance, with a melting point of 6 c 277 f, and a boiling point of 140 c 284 f. A mixed melting point can be taken, by measuring the melting point of a sample composed of roughly equal volumes of the unknown product and of known 3nitrobenzaldehyde ground together well with a mortar and pestle, as in figure 6. Dec 26, 2007 in aspirin assuming you mean the pure compound and not the tablet with the other parts of the formulation, the hydroxyl group is part of an ester of acetic acid. The melting point is the temperature in which aspirin will go from a solid to a liquid. Aspirin is prepared by acetylated salicylic acid i a process called esterification.
Aspirin has different chemical features than any other molecules. An open letter to managers leading distributed teams. Haynes 20 preparing aspirin by reacting salicylic acid and acetic anhydride, and recording its melting point was the. Cox2acetaminophen acts functionally as a selective cox2 inhibitor led us to investigate the hypothesis of whether it works via preferential cox2 blockade. You must cite basic information about the source within the text to let the reader know that youre borrowing from the another authors work. The multitude of synonyms indicates the prevalence of this drug. Search chemicals by name, molecular formula, structure, and other identifiers. A small amount of a strong acid is used as a catalyst which speeds up the reaction. Miscellaneous the melting point of acetylsalicylic acid published by permission of the chairman of the committee of revision, u. The aspirin story experimental and investigation section 2. Fusion melting point data from nist standard reference database 69.
Preparation of aspirin and determination of the melting point. Faculty of engineering university of santo tomas manila, philippines abstract this experiment involved three steps. Although, many substances have similar melting points, so having an idea of possible chemicals in mind can greatly narrow down the choices. Look up the melting points of salicylic acid and a. Upon completion of the lab, analysis, and calculations, it is evident that the synthesis of aspirin is possible using these methods but that the yield will be relatively low. Purity can be determined by identify the melting point of aspirin. You may find information in reference books, in libraries, in pharmacies and by contacting. Apa, apa 5th edition, apa no doi, no issue, bibtex, chicago. Esterification is the reaction of the carboxyl cooh group, and the oh group to form a carboxy. Presents the history of the chemistry and preparation of aspirin. The preparation of aspirin, the recrystallisation of aspirin and the melting point determination of aspirin. This book contains eight freestanding activities that can be used singly or as a coherent package in a wide range of teaching and learning situations for both academic and vocational courses.
To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. Includes eight activities that can be used in a variety of teaching and learning situations. A pure sample of a substance will melt at a sharply defined temperature, an impure sample will show a larger range. Create your citations, reference lists and bibliographies automatically using the apa, mla, chicago, or harvard referencing styles.
Aimed at post16 students in chemistry, this book contains activities for both academic and. Abstract aspirin is the common name for the compound acetylsalicylic acid, widely used as a fever reducer and as a pain killer. The melting point of crude aspirin was measured to be in the 110120 degrees c range. Compare the melting point you recorded to the melting point in the literature. Results and conclusion for aspirin synthesis essay medicine. Aspirin is used medically to reduce fever and pain. Pubchem is the worlds largest collection of freely accessible chemical information. Reasons for a lower value of melting point can be due to the presence of impurities in the product. This bibliography was generated on cite this for me on monday, august 24, 2015. Melting and boiling point the experiment melting point is approximately 5c. Mar 01, 2007 the problem with getting a value for the melting point of an organic substance is the purity of the material. If the product is indeed 3nitrobenzaldehyde, then this mixture would not be a mixture at all. Also, your melting point range may be greater than 2 degrees. Aspirin, also known as acetylsalicylic acid asa, is a medication used to reduce pain, fever.
Save your sample of the aspirin for a melting point determination and further analysis. Haynes 20 preparing aspirin by reacting salicylic acid and acetic anhydride, and recording its melting point was the aim of this experiment. Aspirin is follows aspirin through its birth ancient sumer andor egypt using willow bark as medicinal treatment, childhood purification, chemical synthesis, adolescence the race for monopoly and profit, adulthood most popular drug on the planet, midlife crisis advent of new drugs such as tylenol and ibuprofen, and its sudden discovery that there is life after middleage use as. Pittsburgh pa section on practical pharmacy and dispensing, a. Since you had such a low melting point range and also a very wide range the product acts like a substance that is very impure. I also used melting point determination to give further evidence towards the purity of aspirin. The crc handbook of chemistry and physics hbcp contains over 700 tables in over 450 documents which may be divided into several pages, all categorised into 17 major subject areas. Aspirin melting point essay medicine and health articles. Apa reference list research preparation for bcom accountancy. Find more information about crossref citation counts. Ampicillin is a penicillin betalactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually grampositive, organisms. The synthesis of aspirin is classified as an esterification reaction. According to the melting point values the aspirin product does not resemble from chem 151 at university of arizona.
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