Caffeine (C8H10O2N4 • H2O) has an absorbance of 0.510 at 272 nm and 1 cm optical path in 1 mg / 100 mL concentration solutions. A 2.5 g sample of soluble coffee is diluted with water to 500 mL. Take 250 mL, add 25.0 mL of 0.1 N H2SO4 and dilute it to 500 mL. The absorbance at 272 nm resulting in 0.415. A) Calculate the grams of caffeine per kg of soluble coffee in the sample. The molar mass of caffeine is 212 g / mol.

Caffeine (C8H10O2N4 • H2O) has an absorbance of 0.510 at 272 nm and 1 cm optical path in 1 mg / 100 mL concentration solutions. A 2.5 g sample of soluble coffee is diluted with water to 500 mL. Take 250 mL, add 25.0 mL of 0.1 N H2SO4 and dilute it to 500 mL. The absorbance at 272 nm resulting in 0.415. A) Calculate the grams of caffeine per kg of soluble coffee in the sample. The molar mass of caffeine is 212 g / mol.

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter11: Properties Of Solutions

Section: Chapter Questions

Problem 109AE: Patients undergoing an upper gastrointestinal tract laboratory test are typically given an X-ray...

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