(Solved): Below is a solubility curve for an unknown compound. a. Suppose 15 grams of the unknown is stirred ...

Below is a solubility curve for an unknown compound. a. Suppose 15 grams of the unknown is stirred in $$50\mathrm{mL}$$ of water at $$80^{?}\mathrm{C}$$. Will all 15 grams dissolve? Explain. b. A solution was prepared by dissolving $$5\mathrm{g}$$ of unknown in $$25\mathrm{mL}$$ of boiling water. What temperature would the solution have to be cooled to before crystals began to appear? c. If the solution in the question above were cooled to $$0^{?}\mathrm{C}$$, what mass of unknown would erystallize? What mass of unknown would remain in solution? Show all work. d. Your sulfanilamide contained a blue impurity that remained in the mother liquor after recrystallization. Draw a likely solubility curve on the graph above that represents the blue impurity. 4. Why was it important to wash your crystals with fresh $$95\%$$ ethanol following vacuum filtration and why did it have to be cold?