Investigation 15: Optimizing the Temperature (Part A)

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Analytical Sciences Digital Library

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In Investigation 14 we found that the optimum solvent is 80% methanol and 20% water (by volume) when extracting a 3.00-g sample of Danshen for 5.00 min using 60.0 mL of solvent at a temperature of 60°C and a microwave power of 800 W. Next, we turn our attention to optimizing the temperature of our solvent extraction.

In general, increasing the solvent's temperature improves the solvent's extraction efficiency, although an excessively high temperature may decompose the sample and destroy some or all of its constituent compounds.

Investigation 15

Propose a set of experiments that will effectively and efficiently allow you to optimize the extraction temperature using the solvent selected in Investigation 14. What range of temperatures will you explore? How many samples will you run? Explain the reasons for the range of temperatures and the number of samples you selected.