Chromatography is the technique which is used for separation of those solutes that

Suggest separation technique$(s)$ one would need to employ to separate the following mixtures:
$(a)$ Mercury and water
$(b)$ Potassium chloride and ammonium chloride
$(c)$ Common salt,water and sand
$(d)$ Kerosene oil,water and salt

Which of the following will show Tyndall effect? Why?
$(a)$ Salt solution
$(b)$ Milk
$(c)$ Copper sulphate solution
$(d)$ Starch solution.

Classify each of the following as a physical or a chemical change. Give reasons.
$(a)$ Drying of a shirt in the sun.
$(b)$ Rising of hot air over a radiator.
$(c)$ Burning of kerosene in a lantern.
$(d)$ Change in the colour of black tea on adding lemon juice to it.
$(e)$ Churning of milk cream to get butter.

What volume of ethyl alcohol and water must be mixed together to prepare $250 \, mL$ of $50 \%$ by volume of alcohol in water?

Name the appropriate methods to separate the following:
$(i)$ Nitrogen from air
$(ii)$ Dye from blue ink
$(iii)$ Butter cream from milk
$(iv)$ Ammonium chloride from common salt