 Last but not least, let's do this question. What's the change in temperature between the freezing point of pure water and of a 0.07 molile solution of calcium chloride? So the first thing you want to remember is calcium chloride when dissolved into water goes to the chemical equation for it to dissolve into water. And then you've got to figure out the osmolarity of the solution, thanks to the osmolarity. Now what, how many molile particles do you have? So you've got the molilogy of particles, 1.31 molile of calcium chloride, you've got three particles. And you just multiply that number by 3, 1.07 times 3, 3.21 molile particles. So now you want to do this equation, the change in temperature equals, I mean those numbers, sorry KF, okay? So M here is going to be 3.21 molile, KF has to be given to you, okay? And so does the freezing point of any of these substances. The freezing point of water degrees Celsius is 0 degrees Celsius, okay? And the KF of water is 1.86 degrees Celsius per molile, okay? So all you've got to do here is plug those two numbers in, this there and there, okay? So KF is 1.86 degrees Celsius per 1 molile, multiply that by 3.21 molile, that cancels, cancels. So that's going to equal 0.97 degrees Celsius. So what's the change in temperature between the freezing point and the temperature? Does that make sense? So you just got to remember that formula and all the numbers are given to you.