Impurity

Because the percentage of each compound in the mixture was not given, both the percent yield calculated and yield will contain both the unknown acid and the neutral compound. Since the product from the organic layer was never recrystallized, the impurities in it may have caused the percent yield to be greater than 100%. 12. The melting point range of the unknown acid was 109-116 °C, while the mixed melting point range of the unknown acid with 2-chlorobenzoic acid was 119-124 °C. These two…

1. Introduction Silicified wood is normally formed close to the surface due to the infiltration of buried wood with mineral-rich water and the associated deposition of minerals (Kim et al., 2009). Two typical geological environments have been reported, 1) trees transported by streams and rivers then buried in the fluvial sediments (e.g., Weibel, 1996; Fielding and Alexander, 2001; Parrish and Falcon-Lang, 2007; Hartmann et al., 2010), and 2) ash from volcanic eruptions buries trees while felled…

substitute rite of marriage is absolutely required. In middle India she can first be married to an arrow or wooden pounder” (Douglas 179). This idea affirms that the gender roles of women in marriage act as a structure for society. The ideas of dirt and impurities are constructed by dictating who a woman marries and when a women marries, and determining when it’s acceptable for her to lose her virginity. The structure that is created as a result of these ideas acts as a way to control society…

1) Important solubility characteristics for a solvent to be used in the crystallization of an organic solid that’s contaminated with impurities is that the organic solid should have low solubility at low temperatures in the solvent, but highly soluble at high temperatures. Also, the solvent should allow the impurities to be either completely soluble or completely insoluble at all temperatures. 2) One way to improve our percent recovery is by making a second crop of crystals by removing the…

Recrystallization is used to separate the compound of interest from any other impurities by dissolving a solid in a proper solvent. A proper solvent doesn’t dissolve the solid at room temperature but does dissolve the solid near its boiling point. It is also important that the proper solvent does dissolve impurities at room temperature but does not dissolve impurities near its boiling point. In this experiment, the crystals that were formed from recrystallization were composed…

extraction, and recrystallization, in an effort to isolate and identify three compounds originally dissolved in a mixture. Extraction is used to isolate a specific compound. Recrystallization involves taking a crude compound and removing unwanted impurities so that a more accurate melting point can be taken, leading to a more precise identification of a compound. The overarching goal was to isolate and identify three different unknowns in a given sample using these techniques. There are two…

the experiment. The experimented melting point was 104.2℃, which was less than the expected melting point at 124-126℃ (ChemSpider). This was most likely due to the impurities being present in the sample, and some moisture still being present in the recovered caffeine when the melting point was determined. The source of the impurities was affected by the length of evaporation time causing sublimation of the final product. Improvements to the experiment include adding additional extractions to…

However, the results of the NMR found in the test show a triplet peak at 2.0 (ppm). Although the ideal peak and example peak are not perfectly equivalent, it still shows that the NMR peak had some source of the product there could have just been an impurity left behind.…

of crude oil which is left over from the refining process of petroleum. Bunker fuel is typically a very thick sludge because of the large amount of impurities such as sulfur and nitrogen. These impurities make bunker fuel extremely cheap for ship operators, but has a much more negative effect on the environment, as when the fuel is burnt the impurities are released into the atmosphere.  Rain is naturally slightly acidic because it combines with carbon dioxide when it falls through the…

liquid solution to a pure solid crystalline phase occurs, this phenomenon is called crystallization. Since the impurities are typically present in significantly littler sums than the compound being crystallized, the greater part of the impurities will stay broke up in the dissolvable even when it is cooled. The purified substance can then be isolated from the dissolvable and impurities by filtration. In this experiment, I had done a crystallization of impure sulfanilamide utilizing 95% ethyl…