How will you separate a mixture containing kerosene and petrol (difference in their boiling points is more than $25\,^{\circ}C$),which are miscible with each other?

$A$ child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in the figure. The filter paper was removed when the water moved near the top of the filter paper.
$(i)$ What would you expect to see,if the ink contains three different coloured components?
$(ii)$ Name the technique used by the child.
$(iii)$ Suggest one more application of this technique.

How can we separate a mixture of two immiscible liquids?

Fractional distillation is suitable for the separation of miscible liquids with a boiling point difference of about $25\, K$ or less. What part of the fractional distillation apparatus makes it efficient and provides an advantage over a simple distillation process? Explain using a diagram.

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.

Define chromatography.