Define chromatography.

Why does a copper sulphate solution in water not show the Tyndall effect,while a mixture of water and milk does?

When a bar magnet is brought closer to a mixture of iron filings and sulphur powder,iron particles stick to the magnet,whereas in the case of iron sulphide,no change is observed. When a mixture of iron and sulphur is added to carbon disulphide,sulphur dissolves,whereas in the case of iron sulphide,no change is observed. Justify the statement that the properties of a compound are different from its constituents,while a mixture shows the properties of its constituent elements using the example of iron and sulphur.

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.

How can we obtain pure copper sulphate from an impure sample?

Explain why particles of a colloidal solution do not settle down when left undisturbed,while in the case of a suspension they do.