To test a spectrophotometer’s accuracy, a solution of 60.06 ppm K2Cr2O7 is prepared and analyzed. This solution has an expected absorbance of 0.641 at 350.0 nm. Several aliquots of the solution produce the following absorbance values. 0.640    0.638    0.640    0.639    0.640    0.639    0.638 is there any significant difference between the experimental mean and the expected value at a 99.9% confidence level? Question 21 options: Yes because tcaltcritical No because tcaltcritical

To test a spectrophotometer’s accuracy, a solution of 60.06 ppm K2Cr2O7 is prepared and analyzed. This solution has an expected absorbance of 0.641 at 350.0 nm. Several aliquots of the solution produce the following absorbance values. 0.640    0.638    0.640    0.639    0.640    0.639    0.638 is there any significant difference between the experimental mean and the expected value at a 99.9% confidence level? Question 21 options: Yes because tcaltcritical No because tcaltcritical

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

Chapter34: Particle Size Determination

Section: Chapter Questions

Problem 34.14QAP

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