The concentration of lead in the soil was measured three times. The concentration mean wascalculated to be 52.6753 ppm with a 95% confidence interval of 0.06348298 ppm. Which valuebelow expresses the concentration (mean) with the correct number of significant figures?a. 52.675 ppmb. 52.67 ppmc. 52.7 ppmd. 53 ppm

Number of experiment = 3 Concentration mean = 52.6753 ppm 95% confidence interval = (+-) 0.06348298

Answered: The concentration of lead in the soil…

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 12P

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A 1 mL sample of glycogen was calculated to contain 35 µmol (micromole) glucose. To 1 mL of this sample was added 2 mL of 2 M HCL. It was then hydrolysed by boiling the solution for 15 minutes. After boiling the hydrolysate was cooled and made up with H2O to a final volume of exactly 10 mL. The glucose was measured in this solution and found to have a concentration of 570 µg/mL (microgram/milliliter). i) Calculate the mass (mg) of glucose in the 10 mL of hydrolysate. As the 1mL of glycogen sample was made up to a final volume of 10 mL, this mass of glucose was produced by the hydrolysis of the original 1 mL glycogen sample. ii) Calculate the amount (µmol) of glucose produced by the hydrolysis of the glycogen sample. iii) Calculate the purity of the glycogen used in the sample as % Purity = (moles of measured glucose/ moles of calculated glucose in glycogen) *100 iv) state your answer in a complete sentence.
A 1 mL sample of glycogen was calculated to contain 21 µmol (micromole) glucose. To 1 mL of this sample was added 2 mL of 2 M HCl. It was then hydrolysed by boiling the solution for 15 minutes. After boiling the hydrolysate was cooled and made up with H2O to a final volume of exactly 10 mL. The glucose was measured in this solution and found to have a concentration of 340 µg/mL (microgram/milliliter). i) Calculate the mass (mg) of glucose in the 10 mL of hydrolysate. As the 1 mL of glycogen sample was made up to a final volume of 10 mL, this mass of glucose was produced by the hydrolysis of the original 1 mL glycogen sample. ii) Calculate the amount (µmol) of glucose produced by the hydrolysis of the glycogen sample. iii) Calculate the purity of the glycogen used in the sample as % Purity = (moles of measured glucose/ moles of calculated glucose in glycogen) *100 iv) state your answer in a complete sentence. Show your working out such that the marker can easily understand it.…
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