Answer
a. This forms an unsaturated solution.
b. This forms a saturated solution.
c. This forms a saturated solution.
Work Step by Step
1. Calculate the mass of $KNO_3$ per 100 g of water in each case.
a. $$100 \space g \space H_2O \times \frac{32 \space g \space KNO_3}{200. \space g \space H_2O} = 16 \space g \space KNO_3$$
b. $$100 \space g \space H_2O \times \frac{19 \space g \space KNO_3}{50. \space g \space H_2O} = 38 \space g \space KNO_3$$
c. $$100 \space g \space H_2O \times \frac{68 \space g \space KNO_3}{150. \space g \space H_2O} = 45 \space g \space KNO_3$$
2. If this amount is equal or greater than 32 g, the solubility per 100 g of water, the solution is saturated. If it is not, the solution is unsaturated.
a. 16 g < 32 g: Unsaturated solution.
b. 38 g > 32 g: Saturated solution.
c. 45 g > 32 g: Saturated solution.
