TLC Lab report

Analysis of pure molecules either heterogenous mixture or analysis of pure molecules neither heterogenous mixture nor analysis of pure molecules heterogenous mixture

2. A gas chromatogram of a four-(4)-component mixture had the following areas and retention times (RT). Component ABCD (RT) (min) 2.564 5.241 1.904 3.217 Area (mm²) 2341 1278 4302 1987 A. Which compound do you suspect is the most volatile? Why? B. Calculate the percent composition of component D.

Below are the gas chromatography results of two separate distillations of the same 1:1 mixture of ethanol and 1-butanol. One sample was obtained from the first fraction of a simple distillation and one sample was obtained from the first fraction of a fractional distillation. Identify the peaks in the chromatographs.  Discuss the conclusions you can make regarding simple distillation compared with fractional distillation.  Which method was more successful?

You are carrying out an experiment by analysing alcoholic drinks by gas chromatography. Why is Gas chromatography the best technique used for this analysis? Why is Carbowax a suitable stationary phase for this analysis? What gases are used and what is their purpose and source?

Please see attached image.

Look up the boiling point for each of the following compounds then determine the order that they will elute from the column. Use this elution order to identify the compound in each of the 6 standard chromatograms. Once you have identified the compound in each chromatogram, record its retention time. Compound Structure Compound Name Elution Order (1-6) Non polar → Polar Boiling Retention Time (From Chromatograms) Point Propyl acetate H H. H. Butyl acetate H. H. H H. H H. H. H. Methanol H O- Ethanol 2-butanone H H H. H. 4-methyl-2- pentanone H. H. HH H.

You are an aquatic scientist and tasked to sample water that contains chlorophenols for gas chromatographic analysis from your local waste water treatment plant (WWTP). Using knowledge of sample preparation and chromatograph, how would you sample, preserve and prepare these samples for GC analysis and why GC is the best detection technique?

Q1: The following are relative peak areas for chromatograms of standard solutions of methyl vinyl ketone (MVK) MVK concentration mmol/L 0.5 Relative peak area 3.76 1.5 9.16 2.5 15.03 3.5 20.42 4.5 25.33 5.5 31.97 A sample containing MVK yielded relative peak area of 21.3. Calculate the concentration of MVK in the sample.(use excel)

Qno1: why there is a need of chromatography and chromatography thecniqs. B) when and where we should use normal and reverse phase chromatography

Chromatography 1. External Standard Method A. Calculate the regression equation and the R-squared value. B. Calculate the concentration of cocaine found in the blood samples of the presidentiables. Which presidential candidate “reliably” tested positive for cocaine?   2. Internal Standard Method >Calculate the concentration of party drug X in the blood samples of the presidential candidates. >Suppose the LOD for party drug X is 0.200 ppm, which of the presidential candidates “reliably” tested for party drug X?

19. What is thin layer chromatography (TLC) LEAST useful for from the list below? A) To determine if crystallization or distillation may be more effective for a separation B) To determine the number of components in a mixture C) To determine the appropriate solvent for column- chromatographic separation D) To monitor the progress of an organic synthesis reaction 14. The solubility of salicylic acid in water is 7.8g/100ml at 100°C and 0.25g/100ml at 25°. Estimate how much water is needed to recrystallize a 19g sample of salicylic acid? A) 150ml B) 250ml C) 300ml D) 400ml

Use a suitable model to explain how separation and identification of a mixture of organic compounds can be achieved with a thin layer chromatographic (TLC) technique.

1. From spinach, the chromatographic analysis will yield two major substances: (a) B-carotene (C40H56), which will separate from the spinach mixture to form a yellow band, and (b) chlorophyll A (CSSH72MGN4OS), which will separate from the mixture to form a green band. i. Describe the characteristics and draw structures of these molecules. ii. From the spectrophotometric analysis, what wavelength (Amax) would you expect ß-carotene (C40H56) to absorb? What wavelength would chlorophyll A (CssH72MgN4O5) absorb?

Please answer Questions 5-3, 5-4, and 5-5 (GC Gas Chromatography) 5-2. A sample mixture of ethyl benzoate (bp 212 Celsius) and dodecane (bp 216.2 Celsius) is injected on two GC columns.Column A has DC710 silicone oil as the stationary phase, and column B uses polyethylene glycol as the stationaryphase. Which substance would be certain to elute first from column A and would the same material be expected toelute first from column B? Which column, A or B, would be expected to give the better separation of these two substances? 5-3. Question 5-2 refers to separating a mixture of two high boiling liquids by gas chromatography. These materials havesimilar boiling points. List several GC variables and conditions that would make it easier to separate thesesubstances by gas chromatography. 5-4. Capillary GC columns have better resolution than packed columns even though the enormous surface area provided by the packing material is absent in capillary columns. Why? 5-5. Preparative GC requires…

Differentiate normal phase chromatography from reverse phase chromatography. From which of the two governs the video demonstration in TLC and paper chromatography? How do you say so?

2. Consider the following example GC Chromatogram from a publication about aggression among Mediterranean Acrobat Ants (C. scutellaris). This particular sample was generated by rinsing hydrocarbons from ant exoskeletons. From the chromatogram, what is the minimum number of unique compunds present in the sample? What data led you to that conclusion? (Don't overthink it) 2 8000000 7000000 6000000 5000000 4000000 3000000 2000000 1000000 Counts (Abundance) 5 19 6 7 0 23.00 24.00 10 | 11 13 17 20 14 15 16 12 teel | 22 19 21 ли 25.00 26.00 27.00 Time "Example of a Gas chromatography-Mass spectrography (GS-MS) chromatogram of hydrocarbon molecules in C. scutellaris" by Filippo Frizzi, et.al, in PLoS One is licensed under CC BY 4.0

From a 10-mL sample, a 1-mL aliquot was taken and diluted to 100mL. From this, a 5-mL aliquot was taken and diluted to 20mL.The final 20mL was found to have a concentration of 0.004M analyte X.What is the concentration of analyte X in the 10-mL sample?

Explain the following Chromatography (for drug analysis) Thin-layer chromatography (TLC) Gas chromatography (GC) Liquid chromatography (LC) (i.e, high performance liquid chromatography or HPLC)

Which form of chromatography is INCORRECTLY defined? A. partition chromatography – solute equilibrates between the stationary liquid and the mobile phase B. affinity chromatography – solute binds to a molecule specific for the solute C. molecular exclusion chromatography – solute is separated based on size D. adsorption chromatography – solute is adsorbed into solid particles E. ion-exchange chromatography – solute ions of the opposite charge are attracted to the stationary phase

1a 1b

How can I get question 8 - Calculate the percent error for the separation of your mixture- equation 3 How can I get question 9 - Calculate the mean percent for determinations 1 and 2 - equation 4

please answer a,b,c,d

True or False: Liquid-solid  phase column chromatography is used to separate large up to multigram amounts of mixtures, based on their differences (however small) in polarity.

4. a. What physical property of a compound predicts whether that compound travels slowly or rapidly through a Gas Chromatograph? b. Suppose you injected a sample of 25% compound A. (bp 80 °C), 5% compound B (bp. 40°C) and 70% Compound C (bp 60 °C) on a GC. inject Circle the Chromatogram that actually fits that scenario and cross the other one out. On the correct GC, label the peaks on the chromatogram with the compounds A, B, and C. inject

If an instrument gives a response of 1240 for a standard containing 8 ppm of a substance, how much if this substance is in a sample that gives a response of 1705? Are any assumptions needed?

Column Chromatography Alumina Chromatography Mixture 9:1 Hexanes:Ether 8:2 Hexanes:Ether 1:1 Hexanes:Acetone Amount Used 3.962 g 0.143 g 9.50 mL 9.50 mL 11.00 mL Additional Observations (Color, etc.) BIU X₂ X² → BI IU X₂ X² → BI IU X₂ X² → BI IU X₂ X² → BIU X₂ X² →

B. There was big news all over the internet that the Ponkan oranges that were imported from one of our neighboring counties are heavily contaminated with pesticides. Your lab was asked to analyze these samples using a gas chromatographic procedure. 7. Some samples do not show any signal for the pesticides, your boss told you to use a Solid-Phase Microextraction (SPME) for the extraction procedure. Explain how SPME works and what are the advantages of using this over the liquid-liquid extraction method.

Make a results and discussion in Laboratory Report Format of the following: 1. Separation of mixture using different techniques 1.1 Simple distillation: Water + acetone 1.2 Fractional Distillation: Methanol + ethanol 1.3 Chromatography: Separation of mixture of Red ink and blue ink 2. purification of impure samples by crystallization 2.1 Copper sulfate 2.2 Potash alum 2.3 Benzoic acid

Amino acids and fatty acids do not readily elute from gas chromatography columns even at temperatures above 200 degrees Celsius. What can be done to these biomolecules to allow gas chromatographic analysis?

Classify the stationary phases based on whether they are commonly used in reversed-phase liquid chromatography (RPLC) or normal-phase liquid chromatography (NPLC). RPLC pentafluorophenyl (-(CH₂)3 C6F3) octyl (-(CH₂), CH3) Answer Bank diol (-(CH₂), OCH₂CH(OH)CH₂OH) octadecyl (-(CH₂)17 CH3) phenyl (-(CH₂), C6H₂) NPLC amino (-(CH₂)2NH₂) cyano (-(CH₂)₂C=N)

What is 4c?

please help me find the average and standard deviation