For the analysis below, find one step within design of experiment, interpretation and calculation of the given situation that is not correct. Write the incorrect step, and state why it is not correct. Write how you will change the step to make it correct. Why do you think he made the mistake ? A student will use a solution containing the complex formed between Bi(III) and thiourea (which has a molar absorptivity of 9.32 X 103 L cm-1 mol-1 at 470 nm) for his thesis experiment (investigation of its optical properties). To know the concentration, he used a calibrated UV-Vis spectrophotometer and 1.00-cm cell , and obtained absorbance of 0.528. To determine concentration, he multiplied molar absorptivity by MM of thiourea complex (MM: 437.3 g/mol) and used Beer’s law. The concentration he obtained is 1.99 X 10-7 M solution.

For the analysis below, find one step within design of experiment, interpretation and calculation of the given situation that is not correct. Write the incorrect step, and state why it is not correct. Write how you will change the step to make it correct. Why do you think he made the mistake ? A student will use a solution containing the complex formed between Bi(III) and thiourea (which has a molar absorptivity of 9.32 X 103 L cm-1 mol-1 at 470 nm) for his thesis experiment (investigation of its optical properties). To know the concentration, he used a calibrated UV-Vis spectrophotometer and 1.00-cm cell , and obtained absorbance of 0.528. To determine concentration, he multiplied molar absorptivity by MM of thiourea complex (MM: 437.3 g/mol) and used Beer’s law. The concentration he obtained is 1.99 X 10-7 M solution.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

ChapterA1: Evaluation Of Analytical Data

Section: Chapter Questions

Problem A1.23QAP

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For the analysis below, find one step within design of experiment, interpretation and calculation of the given situation that is not correct. Write the incorrect step, and state why it is not correct. Write how you will change the step to make it correct. Why do you think he made the mistake ? A student will use a solution containing the complex (which has a molar absorptivity of 9.32 X 103 L cm-1 mol-1 at 470 nm)formed between Bi(III) and thiourea for his thesis experiment (investigation of its optical properties). To know the concentration, he used a calibrated UV-Vis spectrophotometer and 1.00-cm cell , and obtained absorbance of 0.528. To determine concentration, he multiplied molar absorptivity by MM of thiourea complex (MM: 437.3 g/mol) and used Beer’s law. The concentration he obtained is 1.99 X 10-7 M solution. Based on information given in previous question, propose the structure/formula of the complex n previous question. pls show your rationale for the…
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