$(i)$ Name a technique to separate a mixture of two or more miscible liquids for which the difference in boiling points is less than $25\, K$.
$(ii)$ Describe the structure of the column used in the above technique. Why is it used?

State whether the following statement is true or false:
The properties that can be observed and specified are called physical properties.

$(a)$ Name the separation techniques which you will apply for the separation of the following mixtures:
$(i)$ Small pieces of metal in the engine oil of a car.
$(ii)$ Fine mud particles suspended in water.
$(iii)$ Oil from water.
$(iv)$ Sodium chloride from its solution in water.
$(v)$ Camphor from salt.
$(vi)$ Wheat grains from husk.
$(b)$ Classify the following as a chemical or physical change:
$(i)$ Water boils to form steam.
$(ii)$ Burning of paper.
$(iii)$ An almirah gets rusted.
$(iv)$ Making a fruit salad with raw fruits.

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

How can we separate a mixture of two immiscible liquids?

Smoke and fog both are aerosols. In what way are they different?