Questions from General Chemistry

Q: An atomic absorption method for the determination of the amount of iron

An atomic absorption method for the determination of the amount of iron present in used jet engine oil was found from pooling 30 triplicate analyses to have a standard deviation s = 2.9 µg Fe/mL. If s...

Q: An atomic absorption method for determination of copper in fuel samples yielded

An atomic absorption method for determination of copper in fuel samples yielded a pooled /reciprocating aircraft engine showed a copper content of 6.87 μg Cu/mL. Calculate the 95% and 99% confidence i...

Q: Write expressions for the autoprotolysis of a. H2O.

Write expressions for the autoprotolysis of a. H2O. b. HCOOH. c. CH3NH2. d. NH3.

Q: How many replicate measurements are needed to decrease the 95% and

How many replicate measurements are needed to decrease the 95% and 99% confidence limits for the analysis described in Problem 5-7 to ± 1.9 μg Fe/mL?

Q: How many replicate measurements are necessary to decrease the 95% and

How many replicate measurements are necessary to decrease the 95% and 99% confidence limits for the analysis described in Problem 5-8 to ± 0.15 μg Cu/mL?

Q: A volumetric calcium analysis on triplicate samples of the blood serum of

A volumetric calcium analysis on triplicate samples of the blood serum of a patient believed to be suffering from a hyperparathyroid condition produced the following data: mmol Ca/L = 3.15, 3.25, 3.26...

Q: A chemist obtained the following data for percent lindane in the triplicate

A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53. Calculate the 90% confidence interval for the mean of the thre...

Q: A standard method for the determination of glucose in serum is reported

A standard method for the determination of glucose in serum is reported to have a standard deviation of 0.36 mg/dL. If s = 0.36 is a good estimate of σ, how many replicate determinations should be mad...

Q: To test the quality of the work of a commercial laboratory,

To test the quality of the work of a commercial laboratory, duplicate analyses of a purified benzoic acid (68.8% C, 4.953% H) sample were requested. It is assumed that the relative standard /reported...

Q: A prosecuting attorney in a criminal case presented as principal evidence small

A prosecuting attorney in a criminal case presented as principal evidence small fragments of glass found embedded in the coat of the accused. The attorney claimed that the fragments were identical in...