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Against each mixture write down suitable methods of separation.
(a) Colored extracts of grass dissolved in ethanol.
(b) Kerosene from Crude oil.
(c) Paraffin from water.
(d) Iron filings from Sulphur powder.
e).Ammonium chloride from Sodium chloride.
(f) Seawater, to obtain salt.
(g) Blue Copper Sulphate crystals from aqueous copper sulphate.

Answer Text:
a).Paper chromatography is the suitable method in this case, this is because this method of separation will involve partitioning of colored substances depending on their solubilities in the organic solvent and ability to stick on the paper, grass has different colored pigments with different solubilities and stickiness.
b).Kerosene and crude oil are miscible liquids, which means they mix to form a uniform solution. However they have different boiling points, which makes it possible for them to be separated using Fractional distillation.
c).Paraffin and water are immiscible liquids, when mixed they form two separate layers and this makes it possible for them to be separated using a separating funnel, where the more denser liquid(water) settles at the bottom and it is drained first leaving the less dense liquid(paraffin) in the separating funnel.
d).Iron fillings are magnetic while Sulphur powder is not, when a magnet is brought closer to the mixture the iron fillings will be attracted to the magnet leaving the Sulphur powder behind. The method suitable is therefore separating using a magnet
e).Ammonium chloride sublimes while sodium chloride does not, heating the mixture, will make Ammonium chloride to sublime leaving sodium chloride behind, this method of separation is called sublimation, which involves a substance changing from a solid to a gas without passing through liquid state.
f).Seawater has dissolved salt, when heated, the water evaporates on reaching its boiling point. This leaves behind crystals of salt formed in the evaporating dish. This method of separation is known as crystallization
g).Aqueous Copper Sulphate contains water of crystallization and to remain with the crystals of copper sulphate, we need to heat the aqueous copper sulphate to evaporate the water of crystallization and have the crystals form, this method is known as crystallization