"i" & "m"-- The X-Factors In Colligative Properties
"m" actually isn't that bad -- it just stands for molality, which isn't so bad as long as you don't confuse it with molarity. "i" however is a different can of worms, and very easy to forget in those boiling point elevation and freezing point depression problems.
Freezing Point Depression
The first of the two colligative properties that most chemistry classes cover, you can use the molality of a solution to figure out what it's freezing point is. Hint: it's always lower than the pure solvent. We can also use freezing point to determine molar mass, which you may very well do in a lab this chapter, so look sharp. And don't forget i!
Boiling Point Elevation
This is the other colligative property that most chemistry classes cover, where you use the molality of a solution to figure out what it's freezing point is. Unlike freezing point, the boiling point actually goes higher. Go figure. This video has lots of examples, including calculating the molar mass using boiling point. And don't forget i!
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