Answer to Question #150947 in General Chemistry for Marwin Ortiz

Question

How many grams of BaCl2 should be added to 300 g H2O so that the freezing point of the solution is lowered to -8.3°C? Assume that the BaCl2 completely dissociates in the solution.

Answer 1

∆T=iKbm.

m=∆T/iKb. = 8.3/3 x 1.86 = 1,4874552 mol/kg.

m=moles of solute/kg of solvent.

1,4874552 x 0.3 = 0,44623656.

0,44623656 x 208 = 92,8172045 g of BaCl2.