Question

You perform recrystallization of 1 g of impure acetanilide from water. The solubility of pure acetanilide in hot water is 55g/L. The solubility of pure acetanilide in cold water at 0oC is 5.3g/L. Taking these data into consideration answer the following questions: What is minimal volume of hot water that is needed to dissolve 2.1 g of pure acetanilide

Answer 1

Answer:

38.32 mL is minimal volume of hot water that is needed to dissolve 2.1 g of pure acetanilide.

Explanation:

Mass of acetanilide to be dissolved in hot water = 2.1 g

Mass of hot water to be used = m

Solubility of acetanilide = 55 g/L

This means that 55 grams of acetanilide dissolves in 1 L of hot water.

Then 1 grams of acetanilide will dissolve in :

$\frac{1}{55}\times 2.1 L=0.0382 L$

0.0382 L = 0.0382 × 1000 mL =38.2 mL

1 L = 1000 mL

38.32 mL is minimal volume of hot water that is needed to dissolve 2.1 g of pure acetanilide.