Assuming that CoCl2 dissociates completely into ions when it dissolves.

Question

With steps plz

Assuming that CoCl₂ dissociates completely into ions when it dissolves.

Find the freezing point of a solution that is made by dissolving 130 grams of CoCl₂, in 1000 grams of water.

Freezing point=....... C

Answer 1

CoCl₂ ==> Co²⁺ + 2Cl^- (note it produces 3 particles)

Freezing point depression:

∆T = imK

∆T = change in temp = ?

i = van't Hoff factor = 3 because it produces 3 particles

m = molal = moles solute / kg solvent = 130 g x 1 mol CoCl2/98.9 g = 1.31 mol in 1000 g = 1.31 mol/kg

K = freezing constant = 1.86º/m

∆T = (3)(1.31)(1.86)

∆T = 7.33º

Freezing point of solution = - 7.33ºC