Lab Technique 2-Spectrophotometer Use in Serial and Parallel Dilutions

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The spectrophotometer is set at 600 nm. The absorbance of each cuvette is read. The data is shown below: Cuvette 1 is the clank Cuvette # ml albumin Absorbance 0. 0.2 .063 3 0.4 .163 4. 0.6 .187 0.8 .253 1.0 .289 Using this data, plot an Excel graph showing absorbance (y-axis) vs ml albumin (x-axis). Find the correlation coefficient (r). R2 > 0.99 = excellent data; r2 0.98-0.95 good data r2 0.94 -0.90 = fair data. How would you describe this data?- To find the relative sensitivity, for each of tubes 2-6 (neglect blank), perform the following operation absorbance (Lowry)/Absorbance (Biuret x 0.5 gram albumin (Biuret)/0.05 gram (Lowry) x 200 ml (Lowry)/100 mL (Biuret). This implifies to Relative sensitivity = 20 dilution factor x absorbance (Lowry)/Absorbance (Biuret). Report your relative sensitivity as an average of all 5 values.

Agilent Technologies Sample ID: Unknown Method Name: Organic FTIR Method McCrory Sample Scans: 64 User: student Background Scans: 64 Date/Time: 2022-03-24 1:33:12PM Resolution: 8 cm-1 Range: 4,000.00 - 650.00 System Status: Good Apodization: Happ-Genzel File Location: C:\Program Files (x86)\Agilent\MicroLab PC\Results\Unknown 11 2022-03-24T13-33-44.a2r 4000 3500 3000 2500 2000 Wavenumber (cm-1) 1500 1000

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Pre-Lab Questions- To be completed BEFORE lab as an entry slip. These questions are based on content presented in the lab procedure and in lecture. 1. Consider the electromagnetic spectrum. (Reference Site) -- Increasing Frequency (v) 10² 10% 10 10² 10% Trays 1044 10 10- 10 UV 30* 10 IR Visible spectrum 10² 10* 30 Microwave FM AM Radio waves 10° 10² 10 H 10² Increasing Wavelength (2)→ 10 Increasing Wavelength in m a. What type of radiation has the longest wavelength? 10 10² 10 voto b. What type of radiation has the highest energy? Long radio waves c. Looking at the emission line spectrum for hydrogen in Figure 1. Which colored line corresponds to the emission of the highest-energy photon?

3) 3-Methylbutyramide 100 relative intensity .8888 relative abundance .88 CHINO 101 298 888 mass charge (m2) CaH₁N 60 4) n-Butylamine 100 60 CHOCHOCHS R98 8 mass charge (m/z) MW=101.15 MW-73.13

Question:  Using a sample of aspirin for HPLC analysis. If the aspirin was contaminated (wet) with trace amounts of a solvent such as ethyl acetate, hexane, or water, would this contaminant be detected and appear as a peak in the HPLC chromatogram? Briefly explain based on the type of detector used in HPLC analysis and what type of compounds can be detected. My Answer: The HPLC analysis detects chromophores, compounds with multiple double bonds. Since water, ethyl acetate, and hexane all lack multiple pi bonds this will not be detected in the HPLC.  -Question for you, is this complete (and correct), and should I include anything about UV detection? Is UV detection used in HPLC? I thought it was only used on TLC to show compunds that arent visable.

If the peak width w of both Peak 1 and Peak 2 fro eon 1g is 0.5 minutes, what is the resolution factor between the two peaks? 1.13 Selectivity is Peak 1 (6.0 min, Peak 2 w=0.5 (6.8 min, w=0.5 25 min) min) 20 15 Hold up peak (1.8 min) 10 0. 0. 4. 8. time (minutes) 2. 5. Signal

St. John's University Department of Chemistry CHE2241L Date 427/2022 8:00AM Organic Lab Final Exam NAME 1) The attached picture shows the structure of aluminum oxide the column chromatography stationary phase that we used to separate fluorene from fluorenone. Iis this compound a) Polar 5) Nonpolar Explain why it is polar or nonpolar. It is because 2) Safety: Which of the following chemicals are extremely flammable: a) diethyl ether b) acetone c) methanol d) benzyl alcohol e) All of the above except d.

The aspirin we made in lab gad 125-133 melting point and I attached the IR. Base on this information, does it mean we made aspirin? The percent yield was also less than 50. Is that acceptable? Is this aspirin pure or not? please explain your answer.

IR Spec question: https://webbook.nist.gov/cgi/cbook.cgi?ID=B6007500&Mask=80  The spec is chloroform, deutero.  I don't know what the peaks are around 3200 cm-1, 3000 cm-1 and 2300 cm-1.

This was a fractional distillation lab separating cyclohexane and toluene. I know A in the NMR analysis is the aromatic component of toluene but I am having a hard time figuring out the other two peaks. Which one represents the methyl group of toluene and what is the other peak (it might be water or some other impurity)?

NAME: LAB SECTION: EXPERIMENT 21: Spectroscopy of Dyes POSTLAB EXERCISE 1. AUV/V is a spectrometer used to measure the absorbance of a solution of hemoglobin bound to oxy- gen at 590 nm. The molar absorptivity was determined to be 8.57 × 104 M-'cm-. The cuvette used had a 1.00-cm sample pathlength. The measured absorbance was ), 140. What was the concentra- tion of hemoglobin in the solution? 2. What would be the absorbance of the solution in question 1 if the pathlength were 2.00 cm? nohntooote 196

I need help finding the %Composition for %cychohexane and %toluene. The formula (area of peak/total area) * 100%

Spot in R lane Spot in Y lane Upper spot in U lane Distance traveled by spot (cm) Lower spot in U lane 3.00 Spot in B 5.00 lane 1.20 4.70 2.90 Solvent Rf front (cm) 5.90 5.90 5.90 5.90 5.90 Based on your TLC, which best describes the identity of the unknown food dye?

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?

Page of 5 O + 3 ZOOM Question 1: Using a well-known protein estimation technique, absorbance reading for a set of standards were obtained. You were required to plot the data. Which graph would you use? Plot the data using the graph type. Protein Absorbance concentration (mg/mL) (a.u.) 0.01 0.05 0.12 5 10 25 0.25 0.63 1.25 50 Question 2: Enzymes are biological catalysts and perform important biochemical reactions in the body. A group of scientists discovered a new enzyme – Enzyme X. To understand the working of this enzyme, they performed biochemical assays to assess the activity of the enzyme. The results for which are shown in the table below. Based on the information provided in the table, please state which graph would you use? Plot the data using the graph type. Enzyme activity (%) 35 55 pH 3 4 5 68 6 79 7 98 85 20 8 9 10

Here is the protocol for a UV-Vis spectrophotometer to detect water and chlorine-carbon. 1.Dissolve the water and chlorine-carbon compounds in a solvent, such as water. 2.Prepare a standard solution of known concentration that is similar to the sample being measured. 3.Calibrate the spectrophotometer using the standard solution. 4.Measure the absorbance of the sample using the spectrophotometer. 5.Calculate the concentration of the compounds in the sample using the calibration curve obtained from the standard solution. How is the spectrophotometer calibrated with standard solutions? When is the blank solution placed in the spectrophotmeter?

Please do 17. Thank you.

To determine the amount of copper and the identity of the copper compound in the unknown sample, a 100-mL solution containing 120.8 mg of the sample was initially prepared. Then, 5.00 mL of this solution was pipetted and diluted with deionized water in another 100-mL volumetric flask. The absorbance of this diluted solution was determined three times at the analytical wavelength. The data is in the table below.  Unknown sample Trial 1 Trial 2 Trial 3 Absorbance (AU) 0.388 0.389 0.388 What is the Corrected Absorbance of each trial? How do you get the corrected absorbance?

To determine the amount of copper and the identity of the copper compound in the unknown sample, a 100-mL solution containing 120.8 mg of the sample was initially prepared. Then, 5.00 mL of this solution was pipetted and diluted with deionized water in another 100-mL volumetric flask. The absorbance of this diluted solution was determined three times at the analytical wavelength. The data is in the table below.    Unknown sample Trial 1 Trial 2 Trial 3 Absorbance (AU) 0.378 0.379 0.377 What is the corrected absorbance?

To determine the amount of copper and the identity of the copper compound in the unknown sample, a 100-mL solution containing 120.8 mg of the sample was initially prepared. Then, 5.00 mL of this solution was pipetted and diluted with deionized water in another 100-mL volumetric flask. The absorbance of this diluted solution was determined three times at the analytical wavelength. The data is in the table below.  Unknown sample Trial 1 Trial 2 Trial 3 Absorbance (AU) 0.375 0.374 0.376   What is the concentrartion of Cu in the analyzed solution?

Watch the following video (https://fod.infobase.com/OnDemandEmbed.aspx?lti=1&token=166850&wID=97629&loid=0&w=400&h=300) then answer the following questions about the following video. A) Explain in one paragraph why, in your opinion, forensic anthropology and bioarchaeology employ race or ethnicity according with the film. B) Please respond to the following question in one paragraph: When NOVA reconstructs the history of human migration from Africa, it is presenting an antiquated theory of how people arrived in the Americas.  Which model did they put forth?  What is the most recent theory and evidence?  Reference your work.

use the following chromatogram and table as your data. VWD: Sgrad A 284 nm Retention Time 40- -40 20 20 5 10 15 20 25 30 35 Minuteo VWD: Signal A, 284 nm Retention Area Identity Time (min) 7.867 3214697 Vitamin A 8.493 15687 19.410 140354 19.710 64346 20.803 884315 Vitamin E 21.640 36745 22.100 63054 8.403 L98 ÞI 20.803 ; 84年 81

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LOD 秀寸怀 /% D 4000 тр 3000 2000 1500 1000 500 波数/cm² 3398 66 3073 72 3065 74 3047 74 3011 74 2947 70 2929 62 2854 74 1440 64 1203 68 629 77 1712 4 1611 44 1600 67 1589 60 1474 64 1433 57 1175 6B 824 77 1405 74 1398 1149 64 761 35 70 1101 79 671 72 1328 55 1088 70 566 72 1277 41 1035 58 560 74 1463 6D 1244 68 1014 7D 466 60

Interpret the IR spectra that have been gathered.

Table 1: Chromatography Results Mobile Phase: Distilled Water Solvent front distance (cm): 8 cm   M&M Candy Separated Spot Color Migration Distance (cm) (distance to center of spot from origin) Red M&M Red 7.5 cm             Green M&M Yellow 5.3 cm   Blue 7.7 cm       Blue M&M Blue 7.8 cm             -please help with this part Calculations/Results:             Table 1: Results with Distilled Water M&M Candy Separated Spot Color Rf Value   Red M&M                 Green M&M                 Blue M&M                             Rf = Distance traveled by component in a given time/                       Distance traveled by solvent in same time             Show work with units for one sample calculation.

The methodology of choice for measuring therapeutic drug levels is   Question 4 options:   immunoassay   chromatography   atomic absorption spectrophotometry   spectrophotometry

Select all of the atomic-scale pictures that could correctly represent the given balanced chemical equation. A2(g) + 2B(g) 2AB(g) 2:41 PI 11-Mar-2 1LECTION 17 19 T no 12/A prt sc delete $7 %23 & * 8 %3D

Do your graphs show the trends a)you expected based on what you know about absorbance and transmittance using a spectrophotometer? Why or why not? b) why does absorbance data relate more conveniently to concentration that does transmission data?

Answer the questions using one of the words or phrases from the following list. We suggest that you copy and paste answers as it avoids mis-spellings and typos. Accuracy Precision False positive False negative Detection limit Blank Linear range Spike Limit of quantitation Internal standard Please provide the terms for each definition If a patient does not have COVID, but a test results says that they do? How close your experimental result is to the "true" answer? When you run an unknown and then repeat the analysis after adding a known amount of analyte? When you run a solution known to have a zero concentration of your analyte? The lowest concentration of an analyte which can be reported with an accurate concentration? If a patient does have COVID, but a test results says that they do not? How close multiple sample replicate results are to each other? When you run a solution with a known concentration of a compound which is not your analyte? The lowest concentration of an analyte…

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