Preview

Experiment 6

Satisfactory Essays
Open Document
Open Document
471 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Experiment 6
(1) Answer to Question in lab manual. NO introduction/background etc.

1. What is the retention time for caffeine?
Retention time for caffeine : 4.149+4.142+4.152+4.1454 = 4.15 2. What is the retention time for benzoic acid?
Retention time for caffeine : 2.651+2.817+2.857+2.9274 = 2.81

3. How are the retention times for caffeine and benzoic acid related to their chemical structure and the nature of the chromatographic system?
The retention time of caffeine and benzoic are related due to the presence of a hydroxyl group. The hydroxyl group impart polarity and induce dipole-dipole forces between the benzoic acid and the column. Thus, benzoic acid, being polar, are retarded by the column and will come out of the column with a longer retention time. 4. What is the peak width of caffeine?
Peak Width = Area of peakHeight of peak x 2
Peak width of caffeine at 75ppm: 2304120272024 x 2 = 16.94
Peak width of caffeine at 100ppm: 3135638373010 x 2 = 16.81
Peak width of caffeine at 150ppm: 4546077539388 x 2 = 16.86
Peak width of caffeine at 200ppm: 6155195725789 x 2 = 16.96

Average peak width of caffeine: 16.94+16.81+16.86+16.964 = 16.89

5. What is the peak width of benzoic acid?
Peak Width = Area of peakHeight of peak x 2
Peak width of benzoic acid at 75ppm: 56940825861 x 2 = 44.04
Peak width of benzoic acid at 100ppm: 77970236817 x 2 = 43.36
Peak width of benzoic acid at 150ppm: 110568848555 x 2 = 45.54
Peak width of benzoic acid at 200ppm: 148854358107 x 2 = 51.23

Average peak width of benzoic acid: 44.04+43.36+45.54+51.234 = 46.04 6. Calculate the resolution of caffeine and benzoic acid.
R = 2∆tWA+WB = 2(4.15-2.81)46.04+16.89 = 0.043 min/nm 7. Construct a calibration curve of the caffeine peak are versus concentration.

8. What is the linear regression line for the calibration curve of caffeine?

9. Construct a
Continue Reading
View Writing Issues

You May Also Find These Documents Helpful

  • Powerful Essays

    Isolation of Components of Bc Powder
    • 1653 Words
    • 7 Pages

    Isolation of Components of Bc Powder

    Aspirin (1.30 g , 0.00722 mol), Caffeine (0.00666 g, 0.000350 mol) and Salicylamide (0.390 g, 0.00284 mol) were combined in a 100 mL beaker. To this beaker, ethyl acetate (20 mL) and saturated NaHCO3 (10 mL) were added. The organic and aqueous layers were allowed time to separate before the organic layer was removed and put aside. An additional portion of NaHCO3 solution (10 mL) was added and the separation was repeated. The aqueous layer was put aside in a beaker labeled “NaHCO3 Extract.” To the organic layer still in the separatory funnel, 3M HCl (10 mL) was…

    • 1653 Words
    • 7 Pages
    Powerful Essays
    Read More
  • Good Essays

    Caffeine Reaction Lab Report
    • 349 Words
    • 2 Pages

    Caffeine Reaction Lab Report

    After the 10ml of dichloromethane was added to the separatory funnel, two layers began to form. The top layer is the organic layer and contains the caffeine while the aqueous is at the bottom. The dichloromethane has a density of 1.326g/cm so it is denser than water and thus is at the bottom of the funnel. After the distillation , the Bunsen burner was used to sublimate the caffeine as the heating mantle and the water bath would take to long for it sublimate. The text book “Small scale approach to organic laboratory techniques” on pg.77 dictates that “Caffeine constitutes as much as 5% of the leaf material in tea plants.” Using that percentage, this estimates the amount of caffeine in 5 grams of tea leaves is 0.25 grams compared to the actual 0.017grams gained and 6.8% was collected from the 5 grams. This lab performance was better than the acetaminophen lab and overall cooperation of participants was surprising though one of the participants confused the reflux apparatus with the…

    • 349 Words
    • 2 Pages
    Good Essays
    Read More
  • Good Essays

    Experiment 3 prelab
    • 345 Words
    • 2 Pages

    Experiment 3 prelab

    Acquire 40mL of the standard tartrazine solution in a 100mL beaker. Make sure the beaker is clean and dry.…

    • 345 Words
    • 2 Pages
    Good Essays
    Read More
  • Good Essays

    Experiment 13B
    • 972 Words
    • 4 Pages

    Experiment 13B

    A reflux condenser was assembled using a 25-mL round-bottom flask, hot plate, and aluminum block. It was equipped with a drying tube filled with calcium chloride to control vapors. Approximately 2.5 mL of isopentyl alcohol was massed and placed in the round-bottom flask that contained a stir bar. Using the same graduated cylinder, about 3.5 mL of glacial acetic acid was added to the flask. A calibrated Pasteur pipet was used to add 0.5 mL of concentrated sulfuric acid to the flask and the flask was mixed immediately. The flask was connected to the apparatus and covered with aluminum foil to help retain heat. Using rubber tubing, water was circulated into the lower attachment and out the top attachment and the mixture was brought to a boil. After heating under reflux for 60-75 minutes, the flask was removed from the heating source and left to cool down to room temperature. The reaction mixture from the flask was transferred to a culture tube and 5-mL of water was added. Upon addition of water, careful shaking, and occasional venting, the phases separated and the lower aqueous layer was removed and discarded. Using the same procedure as explained above with water, 2.5 mL of aqueous sodium bicarbonate was added and the lower aqueous layer was again removed and discarded. The same procedure was repeated one last time with 2.5 mL of saturated aqueous sodium chloride and the lower aqueous layer was removed and discarded, leaving behind the crude ester. The crude ester was transferred to…

    • 972 Words
    • 4 Pages
    Good Essays
    Read More
  • Good Essays

    1.09 experiments
    • 607 Words
    • 3 Pages

    1.09 experiments

    So my guess was correct again. The blue water did slowly enter the red water.…

    • 607 Words
    • 3 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    Experiment 4a
    • 440 Words
    • 2 Pages

    Experiment 4a

    We placed the zinc inside the beaker and slowly poured the hydrochloric acid into the beaker. As soon as the acid entered the beaker, there was a sizzling sound and bubbles started to form as we add more of the substance in. When the bubbles were forming, we could see a steam of gas coming out of the beaker. After 10 minutes, we noticed bits of zinc were floating on top of the hydrochloric acid and lining the beaker. I lifted the beaker and felt the bottom and it felt warm, which meant the reaction was still happening. After 20 minutes, we added water into the zinc and hydrochloric acid to stop the reaction and we observed a slight cloudy colour (still clear) forming as we slowly pour the water in the beaker.…

    • 440 Words
    • 2 Pages
    Satisfactory Essays
    Read More
  • Good Essays

    Lab experiment 7 questions and conclusion
    • 361 Words
    • 1 Page

    Lab experiment 7 questions and conclusion

    Alpha will turn green on the plate because the bacterium is outcompeting the body for oxygen because there is an iron binding site. Beta hemolysis is cellular death which means that when it is present in the body it is releasing an acidic byproduct or a basic byproduct which will crush the structure of the blood cells. Alpha outcompetes with the blood for oxygen while beta hemolysis kills the competition for blood. Both result in the bacterium obtaining more oxygen for replication. Yes.…

    • 361 Words
    • 1 Page
    Good Essays
    Read More
  • Satisfactory Essays

    Experiment 1 Procedures
    • 537 Words
    • 3 Pages

    Experiment 1 Procedures

    Experiment 1: Bromination of Acetanilide1 Precautions: Ethanol is flammable Sodium hypochlorite is an oxidizing agent and releases toxic fumes (handle in fume hood) Acetic acid is corrosive, harmful if inhaled, flammable and can cause burns (handle in fume hood) Gloves are recommended to avoid chemical contact with skin Reaction Scheme: Conversion of acetanilide to p-bromoacetanilide…

    • 537 Words
    • 3 Pages
    Satisfactory Essays
    Read More
  • Good Essays

    Science Lab 1
    • 699 Words
    • 3 Pages

    Science Lab 1

    1. Make a hypothesis about how you think the two species of Paramecium will grow alone and how they will grow when they are grown together. (Make sure you understand what a hypothesis is before you address this!)…

    • 699 Words
    • 3 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    Experiment E Post Lab
    • 321 Words
    • 2 Pages

    Experiment E Post Lab

    Pyridinium tribromide is considered greener because it has a higher atom economy which means it is closer to an ideal chemical reaction.…

    • 321 Words
    • 2 Pages
    Satisfactory Essays
    Read More
  • Satisfactory Essays

    1.05 Design Your Own Experiment
    • 275 Words
    • 2 Pages

    1.05 Design Your Own Experiment

    Use this document to help you design your experiment about one of the scenarios from the activity. Copy and paste the template then insert your information for each of the steps of the scientific method.…

    • 275 Words
    • 2 Pages
    Satisfactory Essays
    Read More
  • Good Essays

    Experiment 2
    • 864 Words
    • 4 Pages

    Experiment 2

    Remained clear, very bubbly, almost as if forming a gas, which it was. Carbon Dioxide.…

    • 864 Words
    • 4 Pages
    Good Essays
    Read More
  • Good Essays

    Daphnia Lab Report
    • 1045 Words
    • 5 Pages

    Daphnia Lab Report

    After the results had been collected the concentration of caffeine in each solution were given to us, the table will now need to be validated to show the concentrations of each solution.…

    • 1045 Words
    • 5 Pages
    Good Essays
    Read More
  • Good Essays

    Solubility Lab
    • 815 Words
    • 4 Pages

    Solubility Lab

    For part A of the procedure we worked with the solubility of solid compounds in various solvents. The three solid compounds that were worked with during this procedure were benzophenone, malonic acid, and biphenyl. These three solids were then mixed with water (highly polar), methyl alcohol (intermediately polar), and hexanes (nonpolar). When benzophenone is mixed with water the results turned out to be insoluble because benzophenone is a pure hydrocarbon, which are very insoluble in water. When benzophenone was mixed with methyl alcohol, it was soluble because Methanol can hydrogen bond to the carbonyl oxygen of benzophenone. When benzophenone was added to hexanes it was partially soluble because “likes dissolve likes” benzophenone is polar and hexane in non polar. When the next compound, malonic acid was combined with water and with methyl alcohol it turned out to be soluble in both cases. However when malonic acid was combined with hexanes it was in soluble because Malonic acid is polar where as hexane is nonpolar. When the final compound, biphenyl was added to water it was insoluble because biphenyl is a non-polar molecule. Biphenyl was partially soluble when it was added to methyl alcohol but when hexane is added it is soluble because both are non-polar and "likes dissolves likes". For part B of the procedure we worked with the solubility of various alcohols in water and hexane. The three alcohols we used were 1-octanol, 1-butanol, and methyl alcohol. When 1-octanol was added to water it is insoluble because the longer the carbon chain, the more water is repelled. However when 1-octanol was added to hexane it was soluble because it is a polar molecule being that it is an alcohol. When 1-butanol is added to water it is partially soluble because 1-butanol slightly polar. Which means that it was soluble in hexane. When methyl alcohol was added to water it was…

    • 815 Words
    • 4 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    Esterification of P-aminobenzoic acid
    • 485 Words
    • 2 Pages

    Esterification of P-aminobenzoic acid

    P-aminobenzoic acid (1.211g) and absolute ethanol (15mls) were combined with three boiling chips in a 50ml round bottom flask. The round bottom flask was placed on a heating plate and was refluxed starting at 109 ̊C. The solution began boiling at 111 ̊C. It was allowed to reflux for approximately 30 minutes and the solid was dissolved. The round bottom flask was then placed in an ice bath and allowed to cool to room temperature. Concentrated 18 M sulfuric acid (2.4mls) was added to the solution. Then absolute ethanol (3mls) was added to wash the sides of the round bottom flask. The round bottom flask was placed on a heating plate and the solution was refluxed at 120 ̊C, adding an additional absolute ethanol (2mls). The solution was refluxed for 40 minutes and was removed from the heating plate. Distilled water (30mls) was added to the solution. Sodium bicarbonate (60mls) was added dropwise until the pH was approximately 8. The pH was monitored using pH paper. Adding sodium bicarbonate caused a precipitate of benzocaine to form. The precipitate was filtered out of the solution using vacuum filtration. The precipitate was allowed to dry for recrystallization. The product was removed from the filter paper and weighed. The weight of the product was 1.445g. NMR was conducted by mixing the dry product (0.35mg) with duderated chloroform (0.50ml) and mixing until the precipitate dissolved. The sample was then placed into the NMR. The NMR spectrum confirmed the product was benzocaine. The remainder of the sample was placed into a 250ml beaker for recrystallization. Methanol and deionized water were added dropwise while solution was heated on a heating plate. Methanol was added until the product was dissolved. It was removed from the heating plate and allowed to cool to room temperature. It was then placed into an ice bath. Due to the size of the beaker opening the methanol…

    • 485 Words
    • 2 Pages
    Satisfactory Essays
    Read More

Related Topics