Exploring Diversity of Matter by its Chemical Composition (Distillation…
Exploring Diversity of Matter by its Chemical Composition
To separate liquid and insoluble solid mixture
Pouring off the liquid at the top of a container with an insoluble substance (e.g. sand and water mixture)
To separate solutions with different boiling points
A solid that dissolves in a solvent to form a solution can be separated by evaporation. The solvent has to be evaporated away before the solute can be recovered as an undissolved solid.
To separate two miscible liquids that have two different boiling points
Boiling chips are added to ensure smooth boiling
Fractional distillation is used if boiling points of both solutions are quite close
To provide a larger surface for vapour to condense on. Hence other liquids with higher boiling points that happen to form water vapour will condense and fall back down
To separate solutes with different solubilities
The components will move along with the solvent as it moves up the paper. The more soluble ones will move further up with the solvent.
Rf value for component A:
= distance travelled by component A/ distance travelled by solvent