A student carries out the equilibrium constant experiment following a similar procedure used in the LearnSmart Lab simulator. In the first part of the experiment, there is a contaminant which causes absorbance values to read higher than they should for the thiocyanatoiron(III) complex. The resulting Beer's law plot has a slope that is larger than it would be if the contaminant was not present. This results in a Beer's Law plot with a slope that is larger than it would be if the contaminant were not present. If the same contaminant was not present when the student carries out the second part of the experiment, how will the student's results be affected? The molarities of thiocyanatoiron(III) ion would calculate higher and the calculated K̟ values would calculate higher. The molarities of thiocyanatoiron(III) ion would calculate lower and the calculated K, values would calculate lower. The molarities of thiocyanatoiron(III) ion would calculate higher and the calculated K̟ values would calculate lower. The molarities of thiocyanatoiron(III) ion would calculate lower and the calculated K, values would calculate higher.

A student carries out the equilibrium constant experiment following a similar procedure used in the LearnSmart Lab simulator. In the first part of the experiment, there is a contaminant which causes absorbance values to read higher than they should for the thiocyanatoiron(III) complex. The resulting Beer's law plot has a slope that is larger than it would be if the contaminant was not present. This results in a Beer's Law plot with a slope that is larger than it would be if the contaminant were not present. If the same contaminant was not present when the student carries out the second part of the experiment, how will the student's results be affected? The molarities of thiocyanatoiron(III) ion would calculate higher and the calculated K̟ values would calculate higher. The molarities of thiocyanatoiron(III) ion would calculate lower and the calculated K, values would calculate lower. The molarities of thiocyanatoiron(III) ion would calculate higher and the calculated K̟ values would calculate lower. The molarities of thiocyanatoiron(III) ion would calculate lower and the calculated K, values would calculate higher.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter12: Spectrochemical Methods

Section: Chapter Questions

Problem 16P

See similar textbooks

Similar questions

(a) Three components in a mixture have varying distribution constants between the mobile phase and the stationary phase. One of the components has a very high distribution constant. Would this component likely elute first or last and how would you design an experiment or modify the components of the separation to make it perform in the opposite manner? (b) One way to dramatically increase the sensitivity of a quadrupole mass spectrometer is to use a technique called selected ion monitoring (SIM). Explain how this technique works and why it improves sensitivity. Explain what dwell time means. Be sure to draw a diagram and describe how this analysis scheme works. Also, is there a compromise between a wide range of masses scanned and SIM? Explain in easy details.
While cleaning the organic stockroom, a student found a bottle of ethanol labeled "Denatured with Benzene." He decided to determine the concentration of benzene in the ethanol by acquiring the UV spectrum of the liquid in a 2.0 cm cell. The spectrum exhibited an absorption band at 260 nm which was attributable to benzene, and the absorbance of this band was 0.69. In a reference source, the student found that the molar absorptivity of this benzene band in ethanol was 230 M-1cm-1. Show how the student calculated the concentration of the benzene in the ethanol.
A particular substance absorbs very strongly at 620 nm. At a concentration of 0.100 M, this substance has an absorbance of 0.835 at 620 nm. Assuming that the path length is 1 cm, calculate the value of the molar absorptivity coefficient, ε. What would be the absorbance (at 620 nm) of a solution of the same substance with a concentration of 0.140 M using the same path length?
You are working with metal thiocyanate complex, M(SCN)+, with a molar absorptivity constant, ε, of 2700 cm−1M−1 at 500 nm. If you are is using a 1.00 cm cuvette for absorbance measurements at 500 nm, what concentration of M(SCN)+ will give an absorbance value of 0.280?
The red color of soil is often due to the presence of iron. Metal ions are extracted from soil by stirring the soil in acid and then filtering the solution. One method for the analysis of Fe2+ is to form the highly colored Fe2+–thioglycolic acid complex. The complex absorbs strongly at 535 nm. Calibration standards of 1.00, 2.00, 3.00, 4.00, and 5.00 ppm are prepared by transferring appropriate amounts of a 10.0 ppm working solution of Fe2+ into separate 50-mL volumetric flasks, each of which contains 5 mL of thioglycolic acid, 2 mL of 20% w/v ammonium citrate, and 5 mL of 0.22 M NH3. After diluting to volume and mixing, the absorbances of the standards are measured. a)What is the effect on the reported concentration of iron in the sample if there is a trace impurity of Fe2+in the ammonium citrate?
The red color of soil is often due to the presence of iron. Metal ions are extracted from soil by stirring the soil in acid and then filtering the solution. One method for the analysis of Fe2+ is to form the highly colored Fe2+–thioglycolic acid complex. The complex absorbs strongly at 535 nm. Calibration standards of 1.00, 2.00, 3.00, 4.00, and 5.00 ppm are prepared by transferring appropriate amounts of a 10.0 ppm working solution of Fe2+ into separate 50-mL volumetric flasks, each of which contains 5 mL of thioglycolic acid, 2 mL of 20% w/v ammonium citrate, and 5 mL of 0.22 M NH3. After diluting to volume and mixing, the absorbances of the standards are measured. a)Use the data table below to prepare a calibration curve (absorbance versus concentration in ppm). Fit the data to straight line and find the equation for the straight line and the R2 value. (Hint: Think about what to do with the absorbance of the blank.)
The absorbance values observed during the determination of the complex stoichiometry with the Job method using the spectroscopic method were plotted and the following correct equations were obtained. According to this, what is the n value of the compound formed by Fe + 3 and SCN- ions?1. Line equation: y = 2.6188x + 0.1608 2. Line equation: y = -2.5963x + 2.7203
The term masking generally refers to: A) Masking generally refers to the transformation of an interfering species into a form that is not detected. B) Selecting samples from which the identity has been masked. This procedure prevents the analyst from prejudging the outcome of the analysis. C) Removing any material that may interfere with an analysis.
Benzophenone is an aromatic ketone, being an important compound. in organic photochemistry, perfumery and in organic synthesis. benzophenone has an optical absorption band at 340 nm (Λ max) that changes to longer wavelengths when the composite is placed in a polar solvent. What is the prediction you can make of the transition type responsible for this optical absorption and justify your answer
A student is working with a metal thiocyanate complex, M(SCN)+, with a molar absorptivity constant, ε, of 6500 cm−1M−1 at 500 nm. If the student is using a 1.00 cm cuvette for absorbance measurements at 500 nm, what concentration of M(SCN)+ will give an absorbance value of 0.120? [M(SCN)+]=
A student prepares a solution of his dye and measures its absorbance using a 1 cm cuvette. The absorbance is 0.45 and the concentration of the solution is 4.2 * 10-5 M. Determine the molar extinction coefficient at this wavelength (Integer only)
A molecule phosphoresces with a single peak wavelength of 700 nm. The single fluorescence peak is at 590 nm. The absorption peak is at 490 nm. Based on this information, roughly sketch the Jablonski diagram, labeling transitions and calculating differences in each energy state in nm and cm-1. Only typed solution.