Record your hypothesis on page 123. -My hypothesis is we can determine the different between each chemical reaction by the temperature change.To descide which one is exothermic and endothermic. 4. Summarize the procedures you will follow to test your hypothesis. -We measured in each chemical and added water besides, HCl we added NaOH.
A binding material can be separated by dissolving the tablet in ether since three active ingredients are soluble. Then, aqueous K2HPO4 and KOH are used to extract the ether solution with the conjugate base of the Aspirin layer and the conjugate base of the Acetaminophen, respectively. The caffeine can be isolated from the left over layer by evaporating the ether. Two separated solutions form solid by acidifying with HCl and the solid residue can be collected by vacuum filtration. According to the Revell's lab experiment, aspirin, acetaminophen, caffeine recoveries are 60% or higher, <10% and <5%, respectively.
Radu Purtuc | Chemistry 231 - Lab | Section 32 Ronnie :: team-member TECH 705, SEPARATING ACIDS AND NEUTRAL COMPOUNDS BY SOLVENT EXTRACTION - MACROSCALE EXTRACTION July 6, 2006 Lab Report INTRODUCTION Purpose: using extraction technique to separate acetanilide, p-toluic acid, and p-tert-butylphenol; then measure the melting points of each compound and comparing them to the statistical values. Background: separating acids and neutral compounds by solvent extraction is a useful technique used in practice by chemists to separate organic compounds from mixture of other compounds. It generally involve several steps, with limiting factors being the number and output purity of compounds to be extracted from source mixture. A number of specific compound solvents not inter-miscible are used to separate and dissolve compounds, and a physical transfer between solvents is employed. An example of use is cleaning compounds of impurities, where different solvents work as a molecular filter that interacts differentially with compound and impurities respectively.
There are several types of titrations: Acid-base titrations are based on the neutralization reaction between the analyte and an acidic or basic titrant. Redox titrations are based on an oxidation-reduction reaction between the analyte and titrant. Complexometric titrations are based on the formation of a complex between the analyte and the titrant. Ex: the chelating agent EDTA is very commonly used to
Fractions 1,2, and 3 were all separated by column/flash chromatography and their purities were measured with the TLC plate. One suggestion for future labs would be to use more accurate measuring tools. Post lab 1. So the solvent would not reflect the UV rays, therefore creating a dark spot on the luminescent TLC plate. This dark spot helps us measure how much the solvent moved on the TLC plate.
ABSTRACT: The lab of “observations of chemical changes” was to observe the changes that occur in chemical reactions and attempt to interpret these changes. In these experiments it taught me how to interpret chemical reactions with acids and bases. Also, how one chemical can have many different reactions when combined with other chemicals and how to interpret each reaction as what it could mean. I discovered not only how to measure out a well-balanced chemical combination to receive a reaction but to know how to test for acids and bases using a few different methods. Other tests also included in this experiment were testing for Sodium Bicarbonate, and Starch.
In this lab you will use a method called visible spectroscopy to determine the concentration of a solution of CoCl2. This method relies on the fact that colored solutions will
This was done by taking small amounts of the unknown acid. It was then placed into capillary tubes and inserted into the Bibby Sterilin Device. Starting with a high plateau to find a quick melting point and then proceeding to find an actual melting point. The next experiment that aided in finding more characterizations of unknown #2651145-PLF13 was equivalent weight. In order to find the equivalent weight a titration of the unknown acid had to be conducted.
Magic marker inks are often mixtures of several compounds. Paper chromatography is a common method of separating various components of a mixture. After separation, you can observe the different colors that make up a particular color of magic marker ink. You can also calculate a ratio Rf, which compares how far each compound traveled to how far each solvent (substance that dissolves another substance) traveled during the experiment. Rf = Ds/Df Ds = Distance traveled by the compound Df = Distance traveled by the solvent Materials: coffee filter, tape, isopropyl alcohol (rubbing alcohol), water, 3 different color magic markers (not permanent); 3 identical tall, narrow drinking glasses; metric ruler, 3 pencils Pre-lab Questions: List one extensive and one intensive property of marker ink.
The bromine is acting first like an electrophile, and then after bromine has broken the π bond, a carbocation has formed, and a bromide ion has been created, the bromide ion then acts as the nucleophile and forms a bond with the carbocation. This experiment uses bromination, the specific name of halogenation with bromine. In order to for bromination to occur bromine must first be generated. This is done in situ through the oxidation of glacid acetic acid and puridinum bromide perbromide. Once generation is accomplished the available bromine can be brominated.