Help with chemistry

Question

A solution of sodium nitrate, NaNO₃, in 200 g of water is saturated at 50°C. If the solution is cooled to 20°C, how many grams of sodium nitrate will precipitate from the solution?

Answer 1

According to the solubility chart I saw on the web, a saturated solution of NaNO3 at 50 C is about 113 g per 100 g water, so that would be 226 g per 200 g water. At 20 C the solubility is about 176 g per 200 g water. So, if there is no supersaturation, about 50 g NaNO3 will precipitate from solution.