Spectrophotometry Lab (2) (1)

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

In the interference experiment preformed, sodium ascorbate powder was added to water to prepare the stock concentration of the interfering substance. On the package label, the manufacturer states that every 1 gram (1,000mg) of sodium ascorbate powder contains 120mg of sodium and 880mg of ascorbate (vitamin C). How much sodium ascorbate must be weighed out (in milligrams) and added to 100 mL of water in order to have a final stock concentration of pure ascorbate equal to 250 mg/dL?

Question 19 of 27 > Graphs are a common data analysis tool used in all branches of science. The given graph represents how light absorbance at 423 nm varies with concentration of an organic dye. Identify the parts of the graph. Answer Bank y = 0.210x – 0.032 line equation Title Abs423 Dye Conc. (nM) best-fit line 0 i 2 3 4 5 6 7 8 9 10

Chemistry Instrumental Analysis Class The experiment is OES: Cleaning Validation of removal of pharmaceutical drugs and calibration standards by fluoresence spectroscopy - Why the instrument use two detectors and monochromators? What type of monochromators are used in our instrument? - Do you think that a similar experiment can be prepared for the analysis of naproxen and benzoic acid? Explain.

Timer Course Contents » ... » Data, Statistics, and Graphing » Graphing Absorbance (Optical Density) versus Molar Concentration The following table contains some data showing the effect of molar concentration of a solution on the absorbance (optical density) reading from a spectrophotometer. No ↑ Does the solution in your graph follow Beer's Law? Concentration (M) Submit Answer Incorrect. Tries 37/99 Previous Tries 0.13 0.28 0.43 0.58 0.73 0.88 1.03 1.18 1.33 1.48 What is the concentration of a solution that has an Optical Density of 0.21? (Give units in your answer). 0.21M You are correct. Your receipt no. is 155-7520 ? What is the concentration of a solution that has an Optical Density of 0.91? (Give units in your answer). 0.81 M Previous Tries Optical Density To assist in graphing, right click on this excel spreadsheet file, save it to your computer, and open it in Excel. Enter the above data in the appropriate spaces in the spreadsheet. Select the graph that is created, and print…

QUALITATIVE DETECTION OF ORGANIC COMPOUNDS Would you say that all organic compounds give evidence of containing carbon when they are burned or heated?

How does a CEM detector work?

chem 132 Exam 1 2022 • Saved - Search (All+Q) hmdoyle107@gmail.com H Draw Design Layout References Mailings Review View Help Table Design Layout PFind - 12 - A A Aa v A Arial No Spacing Heading 1 & Replace Normal Dictate Sensity Editor R BIU- a x, x A 2. A E= = = E- 2 - H- > Select Paragraph Styles Editing Voice Sensitivity Editor Font Reum 23. Which of the following compounds contain a hemiacetal functional group? OCH3 OH но. OCH3 A OCH3 В OCH3 C a. A and B b. B and C c. B only d. C only 24. Which of the following compounds contains an acetal functional group? OCH3 -OCH3 -OH OCH3 A B a. A and B c. B and C b. A and C d. C only ards OFocus Text Predictions: On Accessibility. Investigate prt sc home end F12 delete insert F3 F8 F4 ES F6 F10 F11 FI & 2 3 4. 6 7 8 9 Q W E R T Y U A S | D G H K C V |N M alt alt ctrl

B.  Quantitative Spectroscopy   Prepare two graphs, %T vs. Concentration and Absorbance vs. Concentration, using the data for the cobalt standards.  The concentrations of Cobalt standards 2-4 can be calculated using simple dilution calculations. Concentration should be on the x-axis for each of these graphs.  The first should clearly show some curvature while the second should be a linear curve. Using the absorbance graph you can determine the concentration of the unknown. Take the absorbance value for the unknown and find that value on the y-axis.  Draw a horizontal line from that point on the y-axis to the plotted line.  From the point where the horizontal line intersects the plotted line, draw a vertical line straight down to the x-axis.  Record the value from the point where you hit the x-axis as the unknown concentration.

100 MASS SPECTRUM 80 60 40 20 0.0 10 20 30 40 50 60 m/z NIST Chemistry WebBook (https://webbook.nist.gov/chemistry) 1. What is the M'? 2. What is the m/z of the base peak? 3. Does it contain chlorine? Explain your answer. Rel. Intensity

Which part of the instrument perform the given function                                                                                   introduction of a micro amount of sample                                                                                   converts sample components into gaseous ions                                                                                   orts the ions according to m/z                                                                                   converts m/z values to electrical signals                                                                                   converts signal/results into a mass spectrum A. mass analyzer B. Vacuum system C. Ion source D. Processor E. inlet system F. detectors

PRE-LAB QUESTIONS Experiment 121 Complete these questions prior to attending lab. Some of the results will be useful in conducting the experiment, so you should record those results in the appropriate section of the lab as well. 1. In Part A, step 1, you are directed to set up the spectrophotometer for measurement of the FeSCN2+ product ion. a. Based on the spectra given here, what would be an appropriate wavelength for the measurement? Review Appendix I if necessary to again familiarize yourself with the issues related to this decision. b. Briefly explain your choice. 0.5 A 0.4 0.3 Absorbance A Absorbance spectra for Fe³+ and FeSCN²+ 0.2 0.1 0 400 0.02 M Fe³+ (dissolved in HNO3) E121-11 0.000048 M FeSCN²+ 500 600 wavelength (nm) 700 2. In Part A, step 4, you will experimentally determine the value of the molar absorptivity, &, for FeSCN2+ at your selected wavelength. Using the Beer-Lambert law, calculate an approximate value for & based on the spectrum of 0.000048 M FeSCN2+ provided…

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?

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 concentration of Cu in analyzed solution (mg/L) for each trial?

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?

A sample solution containing quinine was analysed by fluorescence spectroscopy. 5 mL of the sample solution was diluted with 0.1 M HCl to a final volume of 100 mL. The fluorescence of the solution was measured and gave a value of 54. A reference solution containing 0.086 mg/mL of quinine gave a fluorescence reading of 38. A blank solution gave a fluorescence reading of 21. Calculate the quinine content of the sample solution in mg/mL.

In the HQS-Mg fluorescence part of Lab 6, a calibration curve is made of fluorescence intensity vs. MgCl2 concentration (M). The standard solutions for the calibration curve were made by mixing a small amount of 0.01 M MgCl2 with some HQS solution. Calculate the concentration of MgCl2 (M) in each of the following standards. Report your concentrations to 3 sig figs. Fluorescence Volume of 0.01 M Volume of 1 mM Concentration of MgCl2 (M) Intensity MgCl2 (mL) HQS (mL) 0.031250902 0.8 100 0.049490754 0.8 50 0.059803507 2 100 0.085834029 3.6 100 Hint: The total volume of each solution is volume of 0.01 M MgCl2 + volume of 1 mM HQS.

Copy o B S2 Perfo Student Indeper B Quizzes X Jal [Copy c B 7th Per t.k12.ga.us/d21/Ims/quizzing/user/attempt/quiz_start_frame_auto.d21?ou%=2591470&isprv3D&drc3D0&qi3D2428695&cfql-1&dnb- mochemistry Exam Angel Licona Rivera: Attempt 1 A 71.0 gram gold bar was heated in an experiment and 3,000 J of energy was transferred to the bar. What was the change in temperature for the bar in °C? Specific Heat: (CGold =0.126 J/g°C) Your Answer: Answer units

Document1 - Word Search (Alt+Q) References Mailings Review View Help Write the corresponding letters to the following descriptions. Each proposal can be associated with 0 or 1 match and each letter is not necessarily associated with a proposal. a. [Ar] 4s? b. 1s 2s2p63s23p3 c. 1s2s2p2 d. [Ne] 3s23ps e. [Ar] 4s23d10 f. 1s22s! g. None of those answers 1. I am a halogen 2. I am a transition metal 3. I am alkaline 4. I have exactly 2 single electrons 5. I am the smallest of the atoms presented here 6. I have exactly 3 valence electrons 7.I am the most paramagnetic of the atoms presented here 8. I am the copper 9.I am isoelectronic with Ti2+ IF cessibility: Good to go IA 16 SIS

A student measures the absorbance of a solution in lab a total 4 times and obtained the following results:0.219, 0.224, 0.206, 0.223a. Using the Grubbs test, decide whether any values should be rejected at the 95% confidence level.b. What should the student report as the 95% confidence interval for the absorbance of the solution?

1FbhGb6cd_1-5c/IV_Ivqu J4002epq/z4kbhpYZSIA opy ✩✩ IS Extensions Help I text Calibri. 12 +BIU A d f5 A % 5 T f6 1 5 J 1. Why is it recommended to have a carbon monoxide detector on each floor of a home? Page 4: Water Pollution: Questions i M 6 2. What impact would the increased use of electric vehicles have on environmental damage caused by acid rain? Page 3: More Air Pollution Issues: Questions 4. The COVID-19 pandemic forced many people to work from home for extended periods. During these periods, many cities reported unusually low levels of smog. Suggest an explanation for this observation. 5. Explain how ozone can be both harmful and beneficial. 3. Why is ground level ozone most likely to reach its highest concentrations on hot, sunny days during periods of heavy traffic in large cities? f7 Y []») 3 6. India relies heavily on burning coal to generate electricity. How does India's reliance on coal contribute to the poor air quality experienced in many of India's major cities? & 7 18…

1. Suggest a reasonable combination of ionization source, mass analyzer, and detector for the following applications:   a. The determination of calcium in milk.   b. The identification of a virus with a mass of 30 kDa.   c. The molar mass and structural identification of a newly developed steroid.

O Homework in Chem101 - due Su X My Questions | bartleby ( Periodic Table – Royal Society of how to take a screenshot on an + A learn.maricopa.edu/courses/1132256/modules/items/19018052 CHM151 17003 > Modules > Weeks 8 & 9 - Chapter 7 > Homework in Chem101 - due Sunday night CG 2020 FALL CRED Question 37 of 4 Submit Account Home Complete the balanced neutralization equation for the reaction below: Announcements Dashboa |Modules HCIO-(aq) + CSОН(ag) — rd Concourse Syllabus Courses Grades D2+ N3+ D4+ Cisco Webex Groups 1 2 3 4 7 8 9. Tutoring/Learning Center Calendar Os Do Inbox (s) (1) (g) (aq) History Cs H CI Help • Previous Next » Library 1:03 PM O Type here to search 10/18/2020 +

Question 2 Zinc was analysed in acid mine drainage (AMD). The signal obtained from an AAS for the sample was 0.125 absorbance units. 25.00 mL of a 0.15 ppm Zn standard was added to 75.00 mL of the sample. The signal obtained was 0.750. a. The 0.15 M Zn standard of volume 500 mL was prepared from zinc (II) phosphate. Determine the mass of salt required to make the standard. 4.43 x 10 g -4 b. Determine the Zn concentration in the AMD sample. [Zn] = 0.00619 ppm