(a)
Interpretation:
The total counting rate for sample is 450cpm (sample plus background) and the counting period for this rate is 15.0min. The counting rate for background is 7 cpm for time period 2.0 min. The value of corrected counting rate is to be determined.
Concept introduction:
The following formula will be used for the corrected counting rate-
Where,
(b)
Interpretation:
The total counting rate for sample is 450cpm (sample plus background) and the counting period for this rate is 15.0min. The counting rate for the background is 7 cpm for time period 2.0 min. The value of standard deviation
Concept introduction:
The formula used for the calculation of standard deviation for the corrected counting rate is-
Where,
(c)
Interpretation:
The total counting rate for sample is 450cpm (sample plus background) and the counting period for this rate is 15.0min. The counting rate for background is 7 cpm for time period 2.0 min. The value of 95% confidence interval for the corrected counting rate is to be determined.
Concept introduction:
The formula that will be used-
The formula used for the calculation of standard deviation for the corrected counting rate is-
Where,
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Chapter 32 Solutions
Principles of Instrumental Analysis
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