2.) In a recrystallization process involving sodium benzoate, what is the minimum vol- ume of boiling water needed to dissolve 0.200 g of sodium benzoate? The solubility of sodium benzoate in boiling water is 1 gram per 1.4 mL. About how much sodium benzoate will remain dissolved when the water is cooled to 25°C? The solubility of sodium benzoate at 25°C is 1 gram per 1.8 mL. Calculate the maximum mass of solid sodium benzoate that can be recovered when the cooled solution is filtered.

Minimum volume of water = 0.28 ml

Mass remaining in solution at 25°C = 0.156 g

Maximum mass of sodium benzoate that can be recovered = 0.044 g

Explanation:

solubility of sodium benzoate in boiling water (100°C) = 1 g/1.4 mL

minimum volume of boiling water required to dissolve 0.200 g of sodium benzoate = mass / solubility

minimum volume of water = 0.200 g / (1 g / 1.4 mL)

minimum volume of water = 0.28 ml

Solubility of sodium benzoate at 25°C = 1 g / 1.8 mL

Mass in solution = solubility x volume

Mass in solution = (1 g / 1.8 mL) x 0.28 mL

Mass remaining in solution at 25°C = 0.156 g

Maximum mass of sodium benzoate that can be recovered = 0.200 g -

0.156 g

Maximum mass of sodium benzoate that can be recovered = 0.044 g