Figure 6 shows results for the extraction of Danshen using a range of methanol-water mixtures from 50% methanol to 100% methanol by volume. Each extraction maintains the conditions used for the data in Figures 3–5: a solvent-to-solid ratio of 60.0 mL of solvent and 3.00 g of Danshen, an extraction time of 5.00 min, an extraction temperature of 60°C, and a microwave power of 600 W.
Consider the data in Figure 6 and explain any trends you see in the relative extraction efficiencies using different mixtures of methanol and water. What is the optimum mixture of methanol and water for extracting samples of Danshen? Are your results consistent with your predictions from Investigation 11 and the data from Investigation 12? Why or why not?