The table shows signals from an electrochemical detector for the measurement of mcthane (CH4). CH(%vol) Sign (mV) 0. 0.062 0.11 0.245 0.486 0.971 1.921 1671.9 9.1 47.5 95.6 193.8 387.5 812.5 a) Subtract the blank value (9.1) from all other signal values to obtain the corrected signals. Perform the calibration curve by plotting corrected signal (y) vs CH4 (% vol) (x) in Microsoft excel. Present the graph and the equation of the line given by this program. b) Calculate the uncertainty in y according to the following equation, show the replaced values and the result rounded to 2 significant figures: E(d) Sy = n-2 c) Calculate the uncertainty in b according to the following equation, show the replaced values and the result rounded to 2 significant figures: Sp = Sy %3D D

The table shows signals from an electrochemical detector for the measurement of mcthane (CH4). CH(%vol) Sign (mV) 0. 0.062 0.11 0.245 0.486 0.971 1.921 1671.9 9.1 47.5 95.6 193.8 387.5 812.5 a) Subtract the blank value (9.1) from all other signal values to obtain the corrected signals. Perform the calibration curve by plotting corrected signal (y) vs CH4 (% vol) (x) in Microsoft excel. Present the graph and the equation of the line given by this program. b) Calculate the uncertainty in y according to the following equation, show the replaced values and the result rounded to 2 significant figures: E(d) Sy = n-2 c) Calculate the uncertainty in b according to the following equation, show the replaced values and the result rounded to 2 significant figures: Sp = Sy %3D D

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 4P

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