(a)
Interpretation:
The minimum weight of the sample for relative error due to 0.5 mg loss to be less than 0.1% needs to be determined.
Concept introduction:
The minimum weight is calculated by the relative error formula which is given below-
Here,
(b)
Interpretation:
The minimum weight of the sample for relative error due to 0.5 mg loss to be less than 0.5 % needs to be determined.
Concept introduction:
The minimum weight is calculated by the relative error formula which is given below-
Here,
(c)
Interpretation:
The minimum weight of the sample for relative error due to 0.5 mg loss to be less than 0.8 % needs to be determined.
Concept introduction:
The minimum weight is calculated by the relative error formula which is given below-
Here,
(d)
Interpretation:
The minimum weight of the sample for relative error due to 0.5 mg loss to be less than 1.2 % needs to be determined.
Concept introduction:
The minimum weight is calculated by the relative error formula which is given below-
Here,
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Principles of Instrumental Analysis
- 5-8. A method of analysis yields masses of gold that are low by 0.4 mg. Calculate the percent relative error caused by this result if the mass of gold in the sample is *(a) 500 mg. *(c) 150 mg. (b) 250 mg. (d) 70 mg.arrow_forward(a) For use in an iodine titration, you prepare a solution from 0.222 2 (+0.000 2) g of KIO3 [FM 214.001 0 (+0.000 9)] in 50.00 (+0.05) mL. Find the molarity and its uncertainty with an appropriate number of significant figures. (b) Would your answer be affected significantly if the reagent were only 99.9% pure?arrow_forward1. (a) A solution of NaCl is prepared by dissolving 0.0056 g NaCl with enough H2O in a volumetric flask to yield a final volume of 10 mL. Assuming a standard (0.1 mg) analytical balance and class A glassware is employed, calculate the concentration of the solution (M) and its corresponding error. The atomic weights of Na and Cl are 22.98976928(2) and 34.45(1), respectively (the number in parentheses indicating the error in the last digit). (b) What would the error be if a 1mL transfer pipet was employed (10x) rather than the 10 mL volumetric flask?arrow_forward
- 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 = 3.55, 3.65, 3.14. What is the 95% confidence interval for the mean of the data, assuming(a) No prior information about the precision of the analysis?(b) s → σ = 0.056 mmol Ca/L?arrow_forwardA loss of 0.35 mg of Zn occurs in the course of analysis to determine the element. Calculate the percent relative error due to this loss if the masses of Zn in the replicate samples are the ff: (a) 40.0 mg (b) 400.0 mg (c) 175.0 mg (d) 600.0 mg.arrow_forward(2) In the Analytical Chemistry Laboratory Mr.Yahiya Al Moqbali wanted to prepare KCI solution. He has dissolved 2.634 (+0.002) g of KCI in a 250.00 (±0.08) mL volumetric flask. Calculate the molarity of the solution and express your answer with its absolute uncertainty and give reasonable number of significant figure. [The formula mass of KCI is 74.5513 (±0.001) amu] (Show your Calculation)arrow_forward
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- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning