Construct a calibration curve: (a) Subtract the blank value (9.1) from all other values (this means that your first data point will be 0,0). Then use the LINEST calculation of least squares to find the slope and intercept and their uncertainties. slope 869 intercept (b) Replicate measurements of an unknown gave 152.1, 152.4, 153.9, and 152.7 mV, and a blank gave 9.1, 9.4, 10.6, and 9.0 mV. Subtract the average blank from the average unknown to find the average corrected signal for the unknown. 143.25 Check the number of significant figures. (c) Find the concentration of the unknown and its uncertainty.

Construct a calibration curve: (a) Subtract the blank value (9.1) from all other values (this means that your first data point will be 0,0). Then use the LINEST calculation of least squares to find the slope and intercept and their uncertainties. slope 869 intercept (b) Replicate measurements of an unknown gave 152.1, 152.4, 153.9, and 152.7 mV, and a blank gave 9.1, 9.4, 10.6, and 9.0 mV. Subtract the average blank from the average unknown to find the average corrected signal for the unknown. 143.25 Check the number of significant figures. (c) Find the concentration of the unknown and its uncertainty.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter4: Least-squares And Calibration Methods

Section: Chapter Questions

Problem 9P

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