A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)-- --Absorbance (au) 20- --0.121 30-- -0.302 40- -0.468 50-- -0.573 60- -0.696 70- -0.845 Blank- --0.04 Which of the following is the correct equation for the calibration curve? (A) y = 0.01402 x - 0.1300 B) y = -0.1700 x + 0.01402 y = -0.1300 x + 0.01402 D y = 0.01402 x -0.1700

A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)-- --Absorbance (au) 20- --0.121 30-- -0.302 40- -0.468 50-- -0.573 60- -0.696 70- -0.845 Blank- --0.04 Which of the following is the correct equation for the calibration curve? (A) y = 0.01402 x - 0.1300 B) y = -0.1700 x + 0.01402 y = -0.1300 x + 0.01402 D y = 0.01402 x -0.1700

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter12: Spectrochemical Methods

Section: Chapter Questions

Problem 10P

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Mass spectrometry is an extremely versatile detection system for GC. However, interfacing an HPLC system to a mass spectrometer is a much more difficult task. Describe the major reasons why it is more difficult to combine HPLC with mass spectrometry than it is to combine GC with mass spectrometry.
A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)------------------------Absorbance (au) 20--------------------------------------------------0.121 30--------------------------------------------------0.302 40--------------------------------------------------0.468 50--------------------------------------------------0.573 60--------------------------------------------------0.696 70--------------------------------------------------0.845 Blank----------------------------------------------0.04 Which of the following is the correct equation for the calibration curve?
A chemist prepared a reagent blank and 6 Fe standards with the following concentrations: 20, 30, 40, 50, 60, and 70 ppm. The table below shows the average reading of each run in the UV-Vis spectrophotometer. Concentration (ppm)------------------------Absorbance (au) 20--------------------------------------------------0.121 30--------------------------------------------------0.302 40--------------------------------------------------0.468 50--------------------------------------------------0.573 60--------------------------------------------------0.696 70--------------------------------------------------0.845 Blank----------------------------------------------0.04 Which of the following is the correct equation for the calibration curve? y = 0.01402 x – 0.1700 y = 0.01402 x – 0.1300 y = -0.1300 x + 0.01402 y = -0.1700 x + 0.01402
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