Data Collection Mass of 2 Vivarin tablets (g) 0.728 Mass of crude caffeine (g) 0.567 Mass of recrystallized caffeine (g) 0.519 Calculations Percent by mass of caffeine in Vivarin tablets (w/w%) Percent isolation of caffeine (%) Caffeine melting point (lit) (°C) Caffeine melting point (expected) (°C) - provide an expected melting point of the product. Questions If the solubility of caffeine in water is 2.2 mg/mL at 25 °C,180 mg/mL at 80 °C, and 670 mg/mL at 100 °C, explain why the first step in the separation is to heat the ground up tablets. Normal BIIIU X2| X|> fx Ix 田=|T| 剂二

Data Collection Mass of 2 Vivarin tablets (g) 0.728 Mass of crude caffeine (g) 0.567 Mass of recrystallized caffeine (g) 0.519 Calculations Percent by mass of caffeine in Vivarin tablets (w/w%) Percent isolation of caffeine (%) Caffeine melting point (lit) (°C) Caffeine melting point (expected) (°C) - provide an expected melting point of the product. Questions If the solubility of caffeine in water is 2.2 mg/mL at 25 °C,180 mg/mL at 80 °C, and 670 mg/mL at 100 °C, explain why the first step in the separation is to heat the ground up tablets. Normal BIIIU X2| X|> fx Ix 田=|T| 剂二

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.19QAP

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