Next, about 10 mL of both solutions, Red 40 and Blue 1, were added to a small beaker. The concentration of the stock solution were recorded, 52.1 ppm for Red 40 and 16.6 ppm for Blue 1. Then, using the volumetric pipette, 5 mL of each solution was transferred into a 10 mL volumetric flask, labelled either R1 or B1. Deionized water was added into the flask using a pipette until the solution level reached a line which indicated 10 mL. A cap for the flask was inserted and the flask was invented a few times to completely mix the solution. Then, the volumetric pipette was rinsed with fresh deionized water and
Distillation is used to remove impurities from a mixture – one component of which must be a liquid. Boiling points are utilized in determining the identity of the unknowns. Types of distillation include
To prepare for the lab, fill one 600 mL beaker ⅔ full with tap water (roughly 400 mL full) and place on a hot plate with a thermometer. This beaker’s temperature needs to stay constant at 60℃ so the hot plate settings may need to be adjusted throughout the lab. Next, fill the 1000 mL beaker ⅔ full with cool tap water (roughly 700mL full) and place a thermometer in it. Set this beaker aside and maintain a temperature of roughly 25℃. Place the test tube of benzoic acid/lauric acid in the 60℃ water on the hot plate and when the solid solution begins to melt place the thermometer that was in the water into the test tube. Continue to heat the solution until it reaches about 55℃. Using the test tube holder, transfer the liquefied solution tube to the 25℃ water and record the temperature at 30-second intervals using a clock or stopwatch using a pencil until the solution reaches 35℃ or close to the temperature due to experimental error. While cooling, gently stir the solution using the thermometer until the solution begins to solidify. Once all the data is collected, reheat the solid solution tube in the warm water until it melts and remove the thermometer and wipe it off to avoid the solution adhering to the thermometer. After the data has been recorded, clean-up the lab station and put away the lab
The other group’s simple distillation experiment consisted of the alkane mixture of hexane-heptane. The results of the other group’s mixture were similarly conducted in the same experimental manner, therefore the temperature and the area and time were recorded in a respective manner. The first fraction of the hexane-heptane was recorded to have the temperature ranges of 65.9°C-71.2°C. The peak area of the first fraction appeared to be 65.76% at ———, and 34.24% at ———-. During the second fraction, the temperate ranges was recorded to be 76.4°C-80.2°C. The peak area of the second fraction were 58.77% at ——— and 39.86% at ———-. The third fraction of hexane-heptane was collected, but the sample was not taken for distillation due to the teacher assistant’s specific instructions. The fourth fraction of the hexane-heptane mixture temperature ranges were not available. The peak of the fourth fraction appeared to be 24.29% at ——- and 75.71% at ——-. All three fractions of the hexane-octane mixture that were taken during the experiment were evaluated by a gas chromatogram. The other group’s first graph showed two peaks which consisted of hexane and heptane. The hexane was more dominant in the first graph. However, the second and third graphs showed that hexane’s peak area decreased over time while the area of heptane increased over time. This was due to heptane having a higher boiling point than hexane. Therefore, a larger amount of heptane was distilled and passed through the vessel in the gas
In lab 3, fundamentals of chromatography, the purpose was to examine how components of mixtures can be separated by taking advantage of different in physical properties. A huge process in this lab was paper chromatography, which was used to isolate food dyes that are found in different drink mixes. The different chromatograms of FD&C dyes were compared to identify which dyes are present in each of the mixes. Chromatograms where made for the known FD&C and for the three Kool-Aid samples. The retention factor for each dye was calculated. F or each of the Kool-Aid flavors, 2.0 g was weighed out from the packet and 5mL of water was mixed in with them each. mL of 0.1% NaCl solution was added to 100mL of bottled water. The six chromatography strips
In this lab, there were 4 different distillations that were performed each with the same end goal to separate the two different organic compounds, cyclohexane and toluene. We used the boiling points of the two compounds to separate them using the following 4 techniques: microscale simple distillation, miniscale simple distillation, miniscale fractional packed distillation, and miniscale fractional unpacked distillation. The three different miniscale distillations were used to predict the accuracy of the distillation by comparing them to one other. The most accurate of the three distillations is the miniscale fractional packed distillation because this type uses a Vigreux column instead
In this experiment, Analysis of Gaseous Products, a comparison between the elimination reactions created in the presence of an acidic and basic conditions was observed to be further analyzed through gas-liquid chromatography. These conditions were achieved by acid-catalyzed dehydration of a secondary and primary alcohol and based-induced dehydration of a secondary and primary bromide. As a result of these changing eliminations, gas-liquid chromatography makes it possible to separate and isolate volatile organic compounds to analyze the stereochemistry and regiochemistry of these compounds without decomposing them. Overall, gas-liquid chromatography of these compounds in acidic or basic conditions contributed in the identification and analysis
Many compounds decompose at the temperatures required for efficient GC separation while HPLC separation can be achieved readily. However, GC is particularly useful in detecting residual solvents in formulations and is also invaluable in looking for degradation products. Amines and acids are not separated well by GC because they tend to be too polar.
Distillation is a technique of separating two miscible liquids by their boiling point differences. This experiment uses distillation to separate and identify two unknown compounds. The two types of distillation are simple and fractional. Simple distillation is used to separate miscible liquids that have a boiling point difference of 100 C or more, while fractional distillation is used to separate miscible liquids that have a boiling point difference of less than 100 C. Simple distillation and fractional distillation have two similar but different apparatuses. The fractional apparatus is set up the same as a simple apparatus, but a column packed with steel wool is added in between the boiling
The gas chromatography parameters that were used to obtain the chromatogram for each distillate fraction had an important effect on the retention time, height and area of each component. The attenuation was set to one, which was proportional to the one microliter amount of distillate fraction that was injected. This helped to reduce the signal sent to the recorder, so that the peaks would be seen on the chromatogram. The current was set to 80 MA and the temperature was set to 160˚C. The temperature was set so that it was equal to or slightly above the average boiling point of the sample. The carrier pressure was set to 150 KPa and the sample was sent to column one. The chromatogram produced relayed the retention time, peak number, area, and height. The area is then used to calculate the amount of mols of cyclohexane and toluene, and after, the theoretical
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. Another finding was that the oil at the gasoline stage was brown pinkish and for kerosene it became a grey.
In order to perform this experiment, the students will need a distillation set-up with a connector receiver, an iron ring and stand, a Bunsen burner, a wire gauze, a 250mL round bottom flask, a graduated cylinder, a thermometer, one or two boiling chips, an alcoholic beverage, masking tape, an ice bath, a stirring rod, and, optionally, food coloring. It is imporatnt to avoid playing with the apparatus and equipment so as to avoid breakage and injuries, especially since fire is being dealt with in this experiment.
Two sources of error may have affected the experiment. Firstly, the experiment required volumes of liquid to be recorded while the vapours were distilling. It was impossible to accurately measure the volume of liquid at any given moment, as the meniscus was moving side to side. Secondly, the distillation was ended while there was still liquid in to round bottom flask. The composition and volume of this liquid were unaccounted for in the calculated
Gas chromatography is a very powerful separation technique for compounds that are reasonably volatile. The components of a sample partitions into two phases, the 1st of these phases is a immobile bed with a great surface area, and the other is a gas phase that permeates through the immobile bed. The sample is evaporated and passed by the mobile gas phase or the carrier gas through the column. Samples separates into the stationary liquid phase, based on their solubilities at the given temperature. The components of the sample called solutes or analytes separate from one another based on their relative vapour. This chromatographic process is called elution.
A gas chromatograph (GC) can be utilized to analyze the contents of a sample quantitatively or in certain circumstances also qualitatively. In the case of preparative chromatography, a pure compound can be extracted from a mixture. The principle of gas chromatography can be explained as following: A micro syringe is used to inject a known volume of vaporous or liquid analyte into the head or entrance of a column whereby a stream of an inert gas acts a carrier (mobile phase). The column acts as a separator of individual or chemically similar components. A column is typically packed with a stationary non-volatile matter (stationary phase). The separation occurs due to different interactions of each component with the stationary phase.