The solubility of AlCl3 in the water at 20°C is 45.8 g of solute per 100 g of water. Determine if the following solutions, maintained at 20°C, are either saturated (S) or unsaturated (U).

Question

a) 37.8 g of AlCl3 in 50.0 g of water _________ 

b) 57.0 g of AlCl3 in 200.0 g of water _________ 

Answer 1

37.8 g / 50 g H2O = 75.6 g / 100 g H2O. This is greater than 45.8 g/100 g so it is (S) saturated

57.0 g /200 g H2O = 28.5 g / 100 g H2O. This is less than 45.8 g/100 g so it is (U) unsaturated