0.641 g of a semi-synthetic alkaloid was dissolved in 25 ml of 1% w/v acetic acid and was analysed directly by HPLC. The solution was found to contain 1.42 mg/100 ml of an impurity. What is the level of impurity in % w/w and ppm? Calculate the pH of a buffer system made by dissolving 1.2 g of acetic acid and 0.82 g of sodium acetate in 500 ml of distilled water (pKa of acetic acid = 4.7)

0.641 g of a semi-synthetic alkaloid was dissolved in 25 ml of 1% w/v acetic acid and was analysed directly by HPLC. The solution was found to contain 1.42 mg/100 ml of an impurity. What is the level of impurity in % w/w and ppm? Calculate the pH of a buffer system made by dissolving 1.2 g of acetic acid and 0.82 g of sodium acetate in 500 ml of distilled water (pKa of acetic acid = 4.7)

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.20QAP

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