Q.Liquids having large difference in boiling points are separated by

Distillation separates (i) a volatile liquid from non-volatile impurities, or (ii) two or more liquids with a sufficient difference in boiling point, by boiling the liquid into vapour and then condensing that vapour back into pure liquid.

In simple distillation, used for a single liquid that boils without decomposing, the liquid sits in a round-bottom flask (heated by a water/oil bath or wire gauze) fitted with a thermometer (bulb just below the side arm); vapour passes through the side arm into a water-jacketed condenser, condenses, and trickles into a receiver. A mixture of acetone (b.p. $56\,^\circ C$) and water (b.p. $100\,^\circ C$) can be separated this way, since the two boiling points are far apart: acetone distils first, then water, with receivers swapped in between. …