Please help

the question that I got is:
Calculate how much 95% ethyl alcohol will be required to dissolve 075g sulfanilamide at 78 degree Celsius. Knowing that solubility of sulfanilamide is 210 mg/ml at 78 degree Celsius, 14mg/ml at 0 Degree Celsius.
please explain.

4 answers

You only need to consider the solubility at 78C.

So if you need to dissolve 75 g then you need

75g/0.210 g ml^-1 = 357 ml or 360 ml to 2 sig figs.
thank you!
Than from here I need to find:
Using the volume of solvent calculated in step 1, calculate how much sulfanilamide will remain dissolved in the mother liquor after the mixture is cooled to 0 degree Celsius?
Can you please explain?
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