A saturated solution is a solution in which the maximum amount of solute has been dissolved at a given temperature. Any additional solute will not dissolve and will remain undissolved in the solution.
Example: If you add sugar to water and stir it, initially the sugar dissolves. However, once the water has dissolved the maximum amount of sugar it can hold at that temperature, any additional sugar will remain undissolved at the bottom. This is a saturated solution.
A pure substance is a material made up of only one type of particle, either atoms or molecules, and has a uniform composition. It has definite chemical and physical properties. Pure substances cannot be separated into other substances by physical methods.
Example: Water (H2O), gold (Au), and oxygen (O2) are all pure substances. They contain only one type of molecule or atom.
A colloid is a mixture where one substance is dispersed evenly throughout another, but the particles are larger than those in a solution (1–1000 nm in diameter) and smaller than those in a suspension. These particles do not settle out over time and are not visible to the naked eye.
Example: Milk is a colloid, where fat droplets are dispersed in water. Another example is fog, which is a colloidal dispersion of water droplets in air.
A suspension is a mixture in which the particles of the solute are large enough to be seen by the naked eye and will eventually settle down due to gravity if left undisturbed. The particles in a suspension are larger than 1000 nm in diameter.
Example: Muddy water is a suspension. The solid particles of soil are suspended in the water and can settle out over time, forming a layer of sediment at the bottom.
Which separation techniques will you apply for the separation of the following?
(a) Sodium chloride from its solution in water
(b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride
(c) Small pieces of metal in the engine oil of a car
(d) Different pigments from an extract of flower petals
(e) Butter from curd
(f) Oil from water
(g) Tea leaves from tea
(h) Iron pins from sand
(i) Wheat grains from husk
(j) Fine mud particles suspended in water