Filtration to atmolysis: the principle, the mixture each technique suits, its one real limitation, and the Rf and Graham's-law calculations that get asked.
Unit 5 carries 3 of the 50 chemistry marks; with three chapters sharing them, this one averages one (MEC publishes weights by unit, not by chapter). Every question here is the same question in different clothes: a mixture is described, and the right technique must be named. So read each method by the property it exploits, not by its apparatus.
The MEC scope line runs: Filtration, sublimation, evaporation and precipitation. Simple and fractional crystallisation. Simple, fractional and vacuum distillation. Paper chromatography. Atmolysis. The headings below are its points in MEC's order.
Three ways it comes: recall (what atmolysis separates); understanding (why glycerol is distilled under reduced pressure, why a fractionating column works); application (an Rf from two distances, a Graham's-law ratio, or "how would you separate camphor from sand?").
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