The substances that sublime easily are

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

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

$A$ mixture of sulphur and carbon disulphide is

Give an example each for the mixture having the following characteristics. Suggest a suitable method to separate the components of these mixtures:
$(a)$ $A$ volatile and a non-volatile component.
$(b)$ Two volatile components with appreciable difference in boiling points.
$(c)$ Two immiscible liquids.
$(d)$ One of the components changes directly from solid to gaseous state.
$(e)$ Two or more coloured constituents soluble in some solvent.

$(a)$ $A$ sugar syrup of mass $214.2\, g$ contains $34.2\, g$ of sugar. Calculate the concentration of sugar in the syrup.
$(b)$ What is a solution?