Posted by Frank on .
Calcium chloride has been used to melt ice from roadways. Given that the saturated solution is 32% calcium chloride by mass, estimate the freezing point. Express your answer in degrees Celsius. Assume that calcium chloride behaves ideally in solution.
32% CaCl2 means 32 g CaCl2/100 g soln or
32 g CaCl2 in 68 g water. The moles CaCl2 then is 32g/molar mass CaCl2
molality = moles CaCl2/0.068 kg.
delta T = i*Kf*m
i = 3. solve for delta T and convert to freezing point.