Three students $A, B$ and $C$ prepared mixtures using chalk powder,common salt and milk respectively in water. Whose mixture
$(i)$ would not leave residue on filter paper after filtration?
$(ii)$ would show Tyndall effect?
$(iii)$ would give transparent/clear solution?
$(iv)$ would settle down at the bottom when left undisturbed?
$(v)$ could be filtered by filter paper?

An element is sonorous and highly ductile. Under which category would you classify this element? What other characteristics do you expect the element to possess?

Identify the solute and the solvent for the following mixtures:
$(a)$ Tincture of iodine
$(b)$ Soda water
$(c)$ Sugar solution
$(d)$ Polluted air
$(e)$ Dilute hydrochloric acid

The concentration of a salt solution in terms of mass by mass percentage is $20 \%$ and the mass of the solution is $550 \text{ g}$. Determine the mass of solute present in the solution. (in $\text{ g}$)

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.

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