Lab Report #5 - CHEM 3105

Based on your value of Ksp1 what is the solubility of borax in the room temperature solution? Trial 1: 0.0141 T2: 0.015 AVG: 0.0139  Temp: 293.15K

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 →

What is 4c?

Chemistry Briefly describe the differences between the scanning and SIM approaches with reference to your data. Discuss how and why your scanning (TIC) and SIM (mass chromatograms look different. Pay particular attention to selectivity of compounds detected and signal-to-noise. What are some advantages of SIM? What are some disadvantages?

Tim is interested in analyzing for Pyraclostrobin (pesticide) in strawberries using QuECHers method for extraction and clean up before analysis with HPLC-uv. The concentration of the Pyraclostrobin in the fruits that he sampled is thought to be between 1-10 ng pesticide per g fruit fresh weight. The HPLC-uv instrument he is using has a LoQ of 5 ppb for Pyraclostrobin. Tim is starting out with 500 mg of the sliced fruit

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g) h) i) j) H₂C Ph OCH3 HO OCH₂Ph OSI(CH₂)3 Br PPha + 2 1) "Buli /THF / rt/1.5 h 2) OsO4/ NalO4 acetone /ether LOCH3 -Si(CH3)3 CH3 /nt/1 h CH₂Cl₂-78°C / 15 min PPn, /1₂ (1 eq) imidazoie / THE 0°C - rt

Explain how it is that SPE cartridges & disks allow analysts to more efficiently pre- concentrate analytes from samples where they exist at low concentrations.

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

The following Rf values were computed from a normal phase chromatography experiment. Arrange them from most polar to least polar. I - 0.25 II - 0.84 III - 0.56 IV- 0.67 Group of answer choices II > IV > III > I I > III > IV > II I > II > III > IV IV > II > III > I

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How can you use ion exchange Chromatography to de-ionize water?  Please shortly answer at your own words. Answer should be to the point (specific 4-5 lines).

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.

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2. What are mobile and Stationary phases in a chromatogram? Site their nature.

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.

outline a separation scheme for isolating pure aspirin. lab video: https://www.youtube.com/watch?v=Y4NMpO1xI8U

Use the following information collected from a SIZE-EXCLUSION CHROMATOGRAPHY experiment to  answer the questions below.  MW Standards  Molecular Weight (kDa)  Elution Volume (mL) blue dextran  1000  85 myoglobin  17.2  200 TIM  53.3  178 hemoglobin  62.2  156 IgG  140  122 ATCase  307.9  94 Prepare a graph showing the linear relationship between log function of molecular weight against  Ve/Vo. The R2value must be 0.9 or higher. What is the linear equation from the standards given? What is  the R2value?

In the Thermo Fisher application note about wine analysis (Lesson 3), the following chromatogram was collected of nine components of wine. If peak 3 has a retention time of 3.15 minutes and a peak width of 0.070 minutes, and peak 4 has a retention time of 3.24 minutes and a peak width of 0.075 minutes, what is the resolution factor between the two peaks? [Hint: it will help to review Lesson 2 for this question.] mAU 300 200 100 0 3.22 0.62 1.04 1.24 2.4 2.6 2.8 LO 34 12 ww 3.0 5 3.2 3.4 3.6 3.8 4.0 Minutes 7 8 9 4.2 4.4 4.6 4.8 5.0 5.2

Please find the Rf values of each drug and the name of the unknown sample!

what is the purpose of TLC Separation & Analysis of Analgesics?

analyte concentration(C)(mg/ml) injection volume (ul) elution time (time) peak DAD signal(mAU) caffeine 1 1 4.67 302.85 aspartame 5 1 7.53 15.83 benzoic acid 1 1 8.14 89.98 saccharin 1 1 1.91 84.86 mixture(add everything above with 1:1:1:1 ratio)   1 4.47 69.58 How to get the concentration of the mixture in this case?

thin layer chromatography: What would happen to the Rf value of a compound if you increased the polarity of the mobile phase while using a polar stationary phase?   please help me this question! Thank you a lot

The uses of thin layer chromatography are: 1) To identify unknown compounds 2) Determine purity of products 3) Analyze reaction mixtures 4) To waste time in lab 5) Determine the melting point of the product U 6) Put an astronaut on the moon.

Answer sections C, D and E in the same answer book. Section D (Chromatography) Question 8 The following data were obtained for the analysis of a mixture of compounds (A-D) by HPLC: Peak Retention time (min) | Width of peak base (min) non-retained 2.1 A 6.4 10.51 B 11.3 1.03 C 13.1 1.25 D 21.6 1.62 a) Using peak C. calculate the number of plates (N) in this column. b) For peak D, calculate the capacity factor (k'). c) For peak B and C, calculate the resolution (R).

please answer a,b,c,d

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

Why do we not need "spitless" injection to measure the toluene content of gasoline using gas chromatography?

please help me solve the rest of table Concentration of AR Stock Solution (ppmppm) 21.22     Unrounded Rounded Concentration of AR Stock Solution (μMμM) 42.7461 42.7

See image below

This is the graph for gel filtration chromatography. Can you please explain why the graph has the maximum and minimum peak and relate it with the gel filtration concept such as the volume of elution, molecular weight, and so on. Thank you . Graph for Result 1: (Volume of elution (mL) with 1% bromophenol blue) Volume of Elution (mL) vs Corrected OD 1.789 1.8 1.6 1.4 1.2 0.745 0.8 0.477 0.6 0.379.400.452 0.406 0.393 0.254 d28 0.25 0.4 9:128 0.161 0.115 0.2 0.060 2 6. 10 12 14 16 Volume of Elution (mL) Corrected OD

The following data are from the HPLC assay of paracetamol 500 mg tablets using the calibration curve method: - Weight of active ingredient in powdered tablets taken for analysis: 180 mg • Initial extraction volume: 200 mL - Dilution steps: 10 mL into 100 mL, then 5 mL into 100 mL - Linear equation: y = 12000x - 50 %3! - Area of chromatographic peak for sample is 4750. What is the theoretical concentration in final solution in mg/100 mL? (2 decimal places). Please do not write the units, just numerical value. Answer:

Answer the following questions.