Distillation and IR Spectroscopy
CHE 361L
Christian Johnson
02/17/2018
Introduction The purpose of this lab was to separate an unknown binary mixture by distillation and use IR spectroscopy along with the placement of known functional groups in order to determine the identity of the compounds. Based upon the potential unknown solutions, there are a few specific functional groups that can specifically be targeted in order to accurately depict the identity. The functional groups and specified area on the IR spectrum are located below.
By directly establishing where these certain functional groups are located on the IR spectrum, the identification of the unknown can be confidently established. Each of the potential compounds have a certain feature
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distillate graph, the temperature is at an obvious discrepancy from the known values that were presented. This could be due to the placement of the thermometer. Placing the thermometer too far or not far enough within the apparatus, or even a leak on the clamps could easily cause at least a 10 ˚C discrepancy. With this in mind, the temperature can provide a helpful insight, but the functional groups on the IR spectra can be a better indicator of the identity of the solution.
For distillate 1, the first major peak on the IR spectra arrives at 3500 cm-1 (an O-H stretch), and the second peak is at 1715 cm-1 (a C=O stretch) indicating a ketone functional group. This can mean that the distillate 1 solution contains a large amount of water. The appearance of the distillate would support this. After taking the top-half of this sample to be ran through the spectrometer, it was evident that this part of the distillate contained water with a small portion of an unknown sample. Water could be present due to the flow of the condenser. As the vapor gathers on the surface of the copper wire and moves through the condenser channel, picking up water particles is a very reasonable idea. As far as the unknown sample, it seems to lean towards being 2-Butanone. This is due to its relatively low boiling
In the first part of the experiment, Part A, the standard solutions were prepared. As a whole, the experiment was conducted by four people, however, for Part A, the group was split in two to prepare the two different solutions. Calibrations curves were created for the standard solutions of both Red 40 and Blue 1. Each solution was treated with a serial 2-fold dilution to gain different concentrations of each solution.
This aqueous solution was then heated until all the dichloromethane evaporated off. An error could have occurred at this point in the experiment if the hot plate was too hot. If the hot plate was set above the boiling point of the ketone, the ketone could have evaporated of along with the dichloromethane. This would result in a lower percent yield of the ketone. To prevent this from happening, the hot plate should not exceed 130˚C, so no matter what ketone was isolated, it would not evaporated off.
And this leads to the conclusion that this substance found in the mixture is indeed sodium. Alcohol was also another substance found in the mixture. Its noticeable as it was most likely was fraction 1 in the fractional distillation lab. Sharing a boiling point with alcohol, alcohol being 82 degrees celsius, and fraction 1 being 83 degrees celsius (which i extremely close). The substance, fraction 1, was also as flammable as alcohol is , when testing its flammibility.
Characteristic property- Test 1- distillation Materials: Goggles, 250 ml beaker, 10 ml graduated
Identification of an Unknown Compound using Quantitative and Qualitative Analysis Lauren Tremaglio Chemistry 1011 Lab, Section 16 Instructor: Steven Belina October 3, 2014 Our signatures indicate that this document represents the work completed by our group this semester. Experimental Design and Discussion of Results The objective of this experiment was to identify an unknown compound through quantitative and qualitative analysis. In order to find the identity of the unknown compound, an initial qualitative test for solubility was performed.
Physically, the unknown compound was composed of white, grainy, crystal-like structures. The unknown was also odorless. From these observations, various physical and chemical testing was performed to determine properties of the unidentified compound. A series of solubility tests were performed, as shown in Table 2, and revealed that the unknown compound was soluble in water, but not in Acetone or Toluene.
The dehydration of 2-methylcyclohexanol takes place at the bottom of the Hickman still. As the Hickman still heats up within the sand bath, the products evaporate and travel higher up in the still where they condense into a liquid and fall within the collection ring, thus separating the product from the remaining water. Drierite (CaSO4) is also added as a drying agent to absorb any leftover water within the product. The purity of the product will then be analyzed with infrared spectroscopy, paying attention to OH peak if it is present. Chemical Reactions: Data and Observations: Material Volume Mol.
3mL of the liquid in each of the vials were added into cuvettes and measured in the spectrophotometer. Before each time point the photo spectrometer was zeroed using a cuvette with 3mL of distilled water. If any of the results were considered unusual the machine was zeroed again and the sample was retested. The results from the spectrophotometer test were recorded in a table. The experiment was repeated six times to gain a sample size of six.
(2005) states that all molecules have different boiling points, this is due to the intermolecular forces between the atoms. Therefore, the more intense the intermolecular force is the higher the boiling point, and the lower intensity, the lower the boiling point. This paper aims to discusses the order of the boiling points of 3-methyl-1-butanol and 3-methylbutanal, 1-Hexanol and 1-Pentanol, examining the differences between them. (De Marco et al. 2014). Results Table 1.
Yes, the melting point data does make sense. While the melting point range was close to the given temperature range, the data was still a little lower than expected. This may have been caused by impurities in the product, since impurities cause melting point range to decrease. The product was observed moving up the capillary tube during melting point analysis, which indicates that the product was not completely dry before melting point range was taken. The water in the product evaporated and caused the product to be pushed up.
Next, a 100 mL graduated cylinder was used to measure 60 mL of distilled water. The water was added to the compound and stirred with a glass-stirring rod until dissolved. Next, The flame test required the solution made during the solubility test. The experiment needed a metal wire that was dipped into the solution
The objective of this experiment was to use an aldol condensation reaction to synthesize 3-nitrochalcone from 3- nitrobenzaldehyde. This was accomplished with a Diels-Alder reaction that utilized 3-nitrobenzaldehyde, acetophenone, ethanol, and sodium hydroxide. The mechanism for the synthesis of 3-nitrochalcone is presented in Figures 1 and 2. The alpha carbon on the acetophenone is deprotonated. This is followed by the attack of the alpha carbon anion on the carbonyl carbon on the 3-nitrobenzaldehyde.
As mentioned in number 13, the data for the melting point makes sense because my pure product and given compound almost perfectly matched. 17. Again as explained in number 14, the TLC data made sense because my pure compound and 4-tert-butylbenzyl phenol had similar distances from the solvent origin of the plate. The presence of benzyl bromide and benzyl alcohol also explains how not all the product dissolved in the filtrate.
There are multiple points both at 43°C and at 72°C which indicates that liquid was collected at these temperatures. Based on this information, it would appear that two different liquids were present in solution and that one liquid has a boiling point of approximately 43°C and that the other has a boiling point of approximately 72°C. The literature value boiling point for DCM in is reported to be about 40°C and it is about 80°C for cyclohexane. Based on the graph, DCM was collected from 4 ml to 22 ml, thus 18 ml of DCM was collected.
Rediet Legese iLab Week # 6 CRUDE OIL DISTILLATION Introduction: The aim of this week lab experiment is to experiment distill crude oil and to check how temperature determine the chemical properties of crude oil plus how the boiling point can also show physical properties. They are two major finding in this experiment. he first finding was the point at which the raw petroleum is heated to the point of boiling, at 275 0C, the gas and kerosene oil are refined, however the oil (lubricant ) stays as an unrefined feature oil.