Melting Point Range Lab Report

Melting Point Data Table Compound Aspirin Caffeine Salicylamide Actual MP (ºC) 93 - 98 260 - 262 96 - 102 Expected MP (ºC) 135 236 140 Percent Error (%) ~30% ~12% ~30%

Melting points are indicative of identifying an unknown product and the level of impurity the product contains. In this case, the possible identity of the product based on its melting points are determined by comparing the obtained melting points of the product to the melting points of the five possible products. Two mini capillaries, containing the product only, were used to determine the product’s melting point. For one mini capillary, the temperature range was 132.1-134.2℃, and the product’s melting point for the second minicapillary ranged from 135.1-137.5℃. In addition, melting points were obtained with the product mixed with meso-hydrobenzoin. The temperature range was 135.0-136.0℃ and 135.0-137.5℃. Although the recorded melting point values fall into the racemic range, but the results still indicate that the product is a meso-hydrobenzoin. The melting point values for the product mixed with the meso-hydrobenzoin standard explains that it is unlikely that the product is racemic. The melting point values were two degrees from each other due to the meso-hydrobenzoin standard making

In this lab the melting point for the chemicals Urea and trans-cinnamic acid were observed in five different ratios: : pure urea, pure trans-cinnamic acid, 90% Urea and 10% trans-cinnamic acid, 50% Urea and 50% trans-cinnamic acid, and 10% Urea and 90% trans-cinnamic acid. By melting the substances,

The percent yield from the experiment was 54.4% of the product, which was low. This low percentage yield might occurred due to loss of the product during transferring or weighing. The melting point of the possible

4- chlorobenzoic acid which was the aqueous layer has a theoretical melting point of 240-243°C, the organic layer, 4-chlorobenzyl alcohol has a theoretical melting point of 68-71°C. During our experiment we were unable to collect any data for the organic

Discussion: As seen in the melting point determination, the average melting point range of the product was 172.2-185.3ºC. The melting points of the possible products are listed as 101ºC for o-methoxybenzoic acid, 110ºC for m- methoxybenzoic acid, and 185ºC for p- methoxybenzoic acid. As the melting point of the sample

Identifying this organic acid was an extensive task that involved several different experiments. Firstly, the melting point had to be determined. Since melting point can be determined to an almost exact degree, finding a close melting point of the specific unknown can accurately point to the identification of the acid. In this case the best melting point

Experiment 3: Identification of an Unknown Mixture by Extraction, Recrystallization and Melting Point Determination Alex Presello 103402448 Lab Completed: October 10th, 2014 University of Windsor  Experiment 3: Identification of an Unknown Mixture Abstract The purpose of this experiment was to first, extract two of three possible organic compounds from an unknown organic mixture (#2) and second, to identify them. The two main methods of separation used in this experiment were liquid-liquid extraction and recrystallization. In order to determine the identity of the unknown compounds, their respective experimental melting points were found and compared to the known melting points of compounds based on previous literature.

The purpose of this experiment is to identify unknown substances by finding certain properties that this substance has. Like the density,melting point and the boiling point with these we are able to identify the unknown liquid and unknown solid that we are given. In order to get the density of a liquid we are first going to divide the mass of the liquid by the volume of the liquid in order to get us the density. In order to get the density of a solid we are going to divide the mass of the solid by the volume of the solid in order to get us the density of the solid. Next we are going to want to find the boiling point of a liquid we find this by placing a thermometer and test tube into a beaker with some water in it. Then we boil it and record the data we are going to want to record the start of the boiling and constant temp of the boiling then use this equation ( Start of boiling + constant temp of boiling ) / 2. This will give us our boiling temperature +/- 5 degrees. Finally we are going to want to find the melting point of a solid we do this by placing the tube in the device that determines the melting point of a solid. Then we

1. During the first part of the experiment, it was concluded that given the information of the melting points of maleic acid and fumaric acid, the two unknown substances could be identified. In stating so, maleic acid had the melting point of 132.5 while fumaric acid had the melting point of 287. During the experiment, a pea-sized sample of each substance were collected and melted with a Bunsen burner.

This experiment determined the melting point of pure urea and cinnamic acid, and a mixture of Urea and Cinnamic Acid. Cinnamic Acid showed signs of melting at the temperature of 128C. Then it became completely

Second, the melting point of 122-124 degrees C is close to the benzamide’s melting point of 128-130 degrees C. This indicates that the product was not 100% pure, due to the fact that the final melting point was lower than pure benzamide’s would be. However, it is only 6 degrees difference. This means that there was only a small amount of impurities.

Phenacetin had a sharp melting point range (1.4 oC) meant that there was no trace of impurities. The melting point range of acetaminophen was 154.4-155.1oC what was about 15 oC lower than the literature value (169-172 oC); however, experimental melting point of acetaminophen had a sharp melting point range of 0.7 oC demonstrating that the compound was pure. The melting point of tartaric acid was 154.3-157.5oC what was approximately 17 oC lower than expectation. Tartaric acid’s melting point range was 3.2 oC which was not expected for a pure compound, it might be a human error while observing otherwise it might be a trace of impurity in the compound due to a present of solvent such as water1. The melting point of the 9:1 mixture of phenacetin and acetaminophen was 104.3-114.9oC explaining that impurities had lower and broader melting point range. The possible reason to explain why the overall experimental melting points were consistently lower than expectation was a defect of

Compounds are mixtures made up of two or more substance and they can be determined by using methods such as melting points and boiling points. By finding a melting point, it can determine the type of compound being used and purity of that compound. Compounds that have a higher purity also have a higher melting point and a smaller rage at which it melts. During this experiment, a DigiMelt was used to heat the substances; urea, trans-cinnamic acid, a 50/50 mixture of urea and trans-cinnamic acid and an unknown crystal, to determine the melting range of each sample.

The actual melting point observed for product 1 was 141⁰C, however, we could not determine the actual melting point for product 2 because it was higher than the thermometer could determine. The maximum temperature product 2 reached was 220⁰C. We did not perform the solubility test ourselves, but a classmate’s results show that product 1 was more soluble in water because it dissolved quicker than product 2 did.