(a) the only information about the precision of the method is the precision for the three data. (b) on the basis of long experience with the method, it is believed that s---->σ lindane. (c) If s=0.28 is good estimate of σ, how many replicate measurement should be made in order for the mean for the analysis of sample to be within 0.2% of the true mean 90% of the time.

(a) the only information about the precision of the method is the precision for the three data. (b) on the basis of long experience with the method, it is believed that s---->σ lindane. (c) If s=0.28 is good estimate of σ, how many replicate measurement should be made in order for the mean for the analysis of sample to be within 0.2% of the true mean 90% of the time.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter2: Basic Statistical Analysis With Excel

Section: Chapter Questions

Problem 10P

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In the determination of iron in fortified cereals by atomic absorption, 0.9133 g of sample was weighed. After a previous treatment, it was dissolved and diluted to 100 mL, an aliquot of 25.0 mL was taken, this was diluted to 100 mL and this solution presented an absorbance reading of 0.251. A series of iron standards of the following concentrations were prepared: 0.0; 1.0; 2.0; 2.5 and 3.0 ppm. Whose absorbances were 0.0; 0.241; 0.405; 0.520 and 0.640. Determine the iron concentration in mg/100 g of sample.
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