The solubility of acetanilide in hot water (5.5 g/100 ml at 100∘C) is not very great, and its solubility in cold water (0.53 g/
100 ml at 0 ∘C) is significant. What would be the maximum theoretical percent recovery from the crystallization of 5.0 g of acetanilide from 100 ml water? (assuming the solution is chilled at 0 ∘C).
Initially, there is 5.0 of the acetanilide in 100 mL of water, then the solution is chilled at 0ºC. The solubility represents the amount that the solvent (water) can dissolve of the solute (acetanilide). So, at 0ºC, 100 mL of water can dissolve till 0.53 g of the compound, the rest will precipitate and will be recovered.
So, the mass that is recovered is 5.0 - 0.53 = 4.47 g
The melting point of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium.
