pyridinium hydrobromide perbromide type of stationary phase column length column temperature rate flow of the carrier gas List the 4 general factors that affect the separation obtained on a gas chromatograph What specific technique is used to collect/isolate your purified unknown compound at the end of the recrystallization experiment? suction filtration 14 of 22 4/16/12 9:15 PM StudyBlue Flashcard Printing of Lab Final 2211L UGA
This colligative property is important in many industries, but is clear to see when using ordinary salt to remove ice from steps or a driveway. The water takes salt into solution, which in turn lowers the freezing point of the water, ensuring that even sub-freezing ambient temperatures do not lead to ice buildup anywhere the salt or ice melt was applied. Experimental Procedure: Before any measurements were taken, equipment was set up and calibrated. Using Microlab’s integrated calibration file the thermistor was calibrated in order to obtain accurate temperature measurements. A graph for the data was also set up with time on the x axis in .5 second intervals and temperature on the y axis.
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.
We expect Pentane to be the most ideal because it’s boiling point is the furthest away from the boiling point of water. To test our hypothesis, we used heat to vaporize each gas, an ice bath to cool the gases down and measured the condensed liquid gas to calculate each gas’s constant. Methods: In this experiment, we first measured the mass of an empty flask using
FON241LL Lab 1 SAFETY, EQUIPMENT, AND THE SCIENTIFIC METHOD Name: ___Arielle Lake________ 1. You are working in the laboratory and break a glass test tube. Explain the procedure that should be followed. (5 pts.) You dispose of it in the designated container for broken glass.
Liquids and Solids Purpose: The goal of this experiment is to be able to identify melting/boiling points of substances. We can then use these methods to identify unknown substances because of constants in melting/boiling points. Procedure: 1. Boiling Point a. Begin by adding 1 mL of rubbing alcohol to test tube and attach a thermometer to it.
Overall reaction of the acid-catalyzed dehydration of 2-methylcyclohexanol Figure 2. Reactions for the unsaturation tests Table of Reactants and Products: Table 1. Molecular weight, density, melting point, and boiling point for all reagents used in Experiment #7 – Dehydration of 2-Methylclyclohexanol, Tests for Unsaturation, and Gas Chromatography. Name: | MW (g/mol): | Density (g/mL): | MP (C): | BP (C): | MSDS: | 2-methylcyclohexanol | 114.19 | 0.93 | -38.00 | 165-168 | Irritant, flammable | 95% phosphoric acid | 97.994 | 1.69 | 42.35 | 158 | Corrosive, irritant | 1-methylcyclohexene | 96.17 | 0.81 | -120.4 | 110 | Irritant, flammable | 3-methylcyclohexene | 96.17 | 0.81 | -124.00 | 104 | Irritant, flammable | Procedure: Part One – Dehydration of 2-methylcyclohexanol A microdistillation apparatus was assembled by securing a microdistillation flask to a ring stand and submerging it in an empty heating mantle. A thermometer and Teflon adaptor were tightly sealed into the top of the flask with the thermometer bulb being below the side arm.
1. An introduction for this experiment. Refer to your lab manual on pages x-xi for what an introduction should include and an example. In this experiment, the molecular weight of an unknown solid is determined through the depression of the freezing point of pure p-xylene. When p-xylene is mixed with another substance the freezing point lowers.
A mixture of unknown compounds was separated based on the difference in reactivity (with aqueous acid or base) and in solubility (in aqueous and organic solvents), the separation from one compound from a mixture by this technique is called extraction. The technique of extraction allows for unknown compounds to be identified based on their melting points as well as their reactivity with acid and based. Extraction is one of the most common and most useful techniques in organic chemistry for separating and purifying compounds. Separation by extraction is based on the differences in solubility of compounds in two different, immiscible solvents. Extraction refers to the fact that one compound is removed from a mixture in one solution; therefore
5) Swirled the solution until the NaEDTA (s) dissolved entirely. 6) After dissolving the solid, deionized water was added to the volumetric flask to make 250mL of EDTA solution. 7) This solution (from Step 6) was then transferred to a clean 250 mL Erlenmeyer flask and placed inside the desk for safe keeping; using a cork wrapped tightly in Parafilm. The disassociation of NaEDTA in water is expressed by the following equation: Na2H2EDTA (s) + H2O (l) yields EDTA4- (aq) + 2Na+(aq) + 2H+(aq) Na2H2EDTA (s) has a molar mass of 372.24 g/mol. Procedure - Reacting EDTA with your Zinc ion in Zinc Iodine Purpose; The