$(a)$ Define an element.
$(b)$ Identify non-metals from the following elements: Carbon,Potassium,Silicon,Chlorine,Mercury.

What is distillation? List the two conditions essential for using this as a method of separation of components of a mixture.

What would you observe when:
$(a)$ a saturated solution of potassium chloride prepared at $60^{\circ} C$ is allowed to cool at room temperature?
$(b)$ an aqueous sugar solution is heated to dryness?
$(c)$ a mixture of iron filings and sulphur powder is heated strongly?

$(a)$ Tabulate the differences between a suspension and a true solution with respect to $(i)$ filtration,$(ii)$ transparency,and $(iii)$ stability.
$(b)$ Give two examples from daily life where the Tyndall effect is observed.

Classify the following as sol,solution,or suspension:
$(i)$ Milk of magnesia
$(ii)$ Coloured gemstones
$(iii)$ Aerated drinks
$(iv)$ Emulsion paint

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