Pre-Lab Plan Module #5 Part 1 (1) (1)

Carbon monoxide is another common poison found in the forensic laboratory. Explain how UV-visible spectrophotometry is applied to quantify carbon monoxide in blood samples.

10 Be sure to answer all parts. Covalent bonds in a molecule absorb radiation in the IR region and vibrate at characteristic frequencies. (a) A molecular vibration absorbs radiation of wavelength 129 um. What frequency (in s) correspond to that wavelength? Enter your answer in scientific notation. 12 -1 2.33 X 10 (b) A molecular vibration has a frequency of vibration of 2.786 × 1013 Hz. What wavelength (in µm) corresponds to that frequency? 1.08 um

In order to measure riboflavin in a breakfast cereal, a 5.00-gram sample of the cereal was extracted with acetic acid and filtered. The extract was transferred to a 50.0 mL volumetric flask and diluted to the mark. The sample was transferred to a cuvette and the fluorescence was measured. The instrument read 59 units (Fluorescence units –an arbitrary scale). 24.00 mL of the cereal extract was sample was mixed with 1.0 mL of a riboflavin standard that was 0.500 ug/mL. The fluorescence of this mixture was measured and read 94 fluorescence units. Calculate the concentration of riboflavin per gram of cereal (use µg/gram of cereal).

5 What is the atomic number of a neutral atom that has 8 neutrons and 7 electrons? a.    15b.    8c.    7d.    1 6 Methods that employ separation of the product chemically through precipitation, with purification, drying and weighing of the resultant product: A.    Spectrophotometric analysisB.    Volumetric analysisC.    Gravimetric analysisD.    Gasometric analysis7 Phase changes involving fusion, except:a.    Solid to liquidb.    Liquid to solidc.    Gas to liquidd.    Gas to solid

If the standard addition intercept is the major source of uncertainty, find the uncertainty in the concentration of Sr in tooth enamel in parts per million. Find the 95% confidence interval for Sr in tooth enamel.

How do solvent, temperature, and pH affect fluorescence of fluorophore?

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Just part b!!!

show-all-working-explaining-detailly-each-step Answer should be typewritten using a computer keyboard.

Quinine in a 1.553-g antimalarial tablet was dissolved in sufficient 0.10 M HCl to give 250 mL of solution.A 10.00-mL aliquot was then diluted to 50.00 mL with the acid. The fluorescence intensity for the dilutedsample at 347.5 nm provided a reading of 196 on an arbitrary scale. A standard 100-ppm quinine solutionregistered 125 when measured under conditions identical to those for the diluted sample. Calculate the massin milligrams of quinine in the tablet.

A student uses visible spectrophotometry to determine the concentration of CoCl2(aq)CoCl2(aq) in a sample solution. First the student prepares a set of CoCl2(aq)CoCl2(aq) solutions of known concentration. Then the student uses a spectrophotometer to determine the absorbance of each of the standard solutions at a wavelength of 510nm510nm and constructs a standard curve. Finally, the student determines the absorbance of the sample of unknown concentration. The original solution used to make the solutions for the standard curve was prepared by dissolving 2.60g2.60g of CoCl2CoCl2 (molar mass 130.g/mol130.g/mol) in enough water to make 100.mL100.mL of solution. What is the molar concentration of the solution? a.) 0.200M b.) 0.500M c.) 1.00M d.) 5.00M

An exploration of any one application of Spectroscopy (Absorption or Emission), Mass Spectrometry (MS) - (ANY kind of mass spec)  Pick one location/project/bit of research where the data is used and explore.  Discuss on what is measured (what instrument) and why and how.  You don't have to fully teach the instrument but spend a paragraph giving the very basics of what is measured and how.  And discuss the application you discovered - just find a place the measurement is used and explain what they do - what they measure and when it tells them.

What causes exposure or closeness in humans: [Explain in detail and thenjustify why]a) to an IR lamp?

A calibration curve is made for the absorbance as a function of concentration of blue dye (in mg/L).  The slope of the curve is 0.131; the y-intercept is -0.01869; the correlation is 0.993.  If a consumer sample has an absorbance of 0.120 on the same instrument, what is its concentration of blue dye, in mg/L? a. 0.034 b. 0.935 c. 0.993 d. 1.06

The validation process comprises four main steps that are : hardware validation, software validation, method validation and system suitability. To evaluate a spectrophotometer’s accuracy by measuring absorbance, a solution of 60.06 mg/L K2Cr2O7 in 0.0050M H2SO4 was carefully prepared together with a 0.0050 M H2SO4 as a reagent blank. If the spectrometer’s signal is properly calibrated, it has been reported that this solution should provide an absorbance of 0.640 +- 0.010 at wavelength 350 nm. Which one of the validations mentioned above had been involved in this process? Explain your choice

Which of the two instrumental modes, atomic absorption or atomic emission, results inthe better detection of metal ions in general? Describe the processes that an analyte solution goes through during atomization in the graphite furnace.

How does pipetting laboratory techniques affect absorbance values when using UV-Vis Spectrophotometry?

Please don't provide handwritten solution ....

Specific absorbance is the absorbance of a 1% solution of a given substance. The specific absorbance can be calculated by: A 1% ст C(i % , For the identification of a substance, 0.0482 g of substance has been weighed, which has been dissolved in 50.00 ml of demineralized water. Thereafter, 50.0 µl of this solution has been diluted to 50.00 ml. a UV-wise analysis (A = 249 nm) of this dilution gave an absorbance of 0.925. a) Calculate the concentration of the diluted solution in% (w/v). b) Calculate the specific absorbance of the substance. c) Will it be possible to measure the specific absorbance directly on a 1% solution? Why / why not?

The light absorbance A of a molecule in solution is measured as a function of concentration [X]. [X]/M                             A                            0                                     0 1.0 × 10–4                      0.157 3.0 × 10–4                      0.482 5.0 × 10–4                      0.713 7.0 × 10–4                      1.15 9.0 × 10–4                      1.37 Use spreadsheet software to graph the data and calculate a best–fit linear trendline. What is the equation of the line that best fits the data?   Question 5 options:   A = (1.55 × 103 M–1) [X] + (4.93 × 10–4)   A = (1.13 × 103 M–1) [X] + (2.52 × 10–4)   A = (9.94 × 102 M–1) [X] + (3.81 × 10–4)

26. What exactly is flame atomic absorbtion spectrometer?

A 25.0 mL aliquot was taken from a 500.0 mL sample of tonic water containing an unknown amount of quinine and diluted to a volume of 200 mL. At 347.5 nm, the fluorescence intensity of the diluted sample was measured 85.7 an arbitrary scale. Under similar conditions, a 27.5 ppm standard quinine solution had a fluorescence intensity of 185. Calculate the mass of quinine in the original tonic water sample in mg.  Do not include units in your answer.

What is the importance of the following analytical methods in chemical analysis? i. UV-vis spectrophotometry ii. HPLC iii. GC

Chemistry Common Isotopes and Mass spectrum of element Mo are given below Most common isotopes: Mo-98; Mo-96 Mo-95; Mo-92; Mo-97 ; Mo-100; Mo-94   Calculate the average atomic mass of Mo How the MS determined the relative intensity (Scale of 100) and Isotope abundance (%)? Why absolute intensity was not used? Can detector sensitivity, ICPMS temperature influence the relative intensity? Explain

Which of two instrumental modes, atomic absorption or atomic emission, results in the better detection of metal ions in general? Describe the processes that can analyte solution goes through during atomization in the graphite furnace?

During your experiment, you measure the absorbance of a sample to be 1.362. You have to convert thisabsorbance to methylene blue concentration (in ppm) using the absorbance measurements of two standardsolutions of known concentration:5 ppm: Absorbance 0.55510 ppm: Absorbance 1.211What is, in ppm, the concentration of your sample? Report using 3 decimal figures. Your answer must becorrect to 0.02 ppm

In the equation, A = ebc, what quantity is represented by e? Molar Absorbtivity. Transmittance. Concentration.

Atomic Spectroscopy   (a) In terms of spectral shape, how are atomic spectra different from molecular spectra? What is the source of this difference?   (b) Describe the decision-making process for picking a line for atomic emission analysis of a given analyte.   (c) For quality assurance, spike recovery is not sufficient to establish confidence in an analytical procedure. Explain this statement. What should be done instead to demonstrate satisfactory performance of an instrumental method (including elemental analysis).   (d) Find a literature example of atomic spectroscopy used for elemental analysis. State the operating conditions with sufficient detail to reproduce the analysis; Please answer very soon will give rating surely All questions complete Answer needed Please help me

At what wavelength was Pb determined? What is the slope and  y-intercept of the calibration curve? The researcher determined the Pb content of water sample from a river suspected to be contaminated with Pb from a nearby factory by complexing with cyanidine and the absorbance measured was 0.405. What is the lead content of the water sample?

The intensity of light passing through a 1.00-cm sample of a solution of polystyrene in methyl ethyl ketone was observed to decrease by O.9%. The concentration of the solution was 10.6 kgm-3. Given A =546.1 nm, no= 1.377, and dn/dC" = 2.20x 10-4 %3D m3/ kg. calculate the molar mass of the polystyrene in kg/mol. The relative displacement (r/ro) of bovine serum albumin was observed as a function of time: t (s) 700 3580 4540 5020 r/r. 1.0129 1.0679 1.0871 1.0965 6 260 /s, find the sedimentation coefficient. Assuming Given w = v = 7.34x 10 3 m3 kg and p = 9.93 x 102 kg/m3, diffusivity = 6.97 x 1011 m2/s at 25 °C, determine the molar %3D mass of the sample in kg/mol.

Chemistry What compound is shown in this IR spectrum?

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.