Zahid,
Sure. Although you may find that the liquid isn't exactly boiling at that temperature - it depends.
Say you have a 50:50 mixture of water and ethanol.
At any temperature above their freezing points the headspace above the mixture will be dominated by ethanol vapour (run the Antoine equation to find their partial vapour pressures). So if you can condense just that vapour (on a cryogenic cold-plate for example) you will extract ethanol from the mixture.
This might take a while if you're far from the boiling point of ethanol.
You speed things up by warming the mixture to the boiling point of ethanol, but then you'll see that the boiling point of a *mixture* is not the simple average of the boiling points of the two liquids in it.
http://www.southwolds.co.uk/user/59/48502.pdf
See?
A 50:50 molar mix will boil at about 92°C - sure the ethanol will evaporate, but there will be a non-zero vapour pressure of water.
May I ask what the other liquid is?
Dear Zahid,
I fully agree with James Garry's answer and you should stick to it. I can only give you one practical advice. If you want to evaporate ethanol and remain as much water fraction you should use a fractionating column. It will strenghten the ethanol concentration in the distillate and will reflux the water back to the kettle. If you'll be diong it in a lab a simple Vigreoux column will do the work. Just remember to choose the appropriate column height to the volume of the sample. You can do it also under vacuum which will bring the boiling point of the mixture a little bit lower.
Regards
Witek
Dear Zahid,
I agree with Witold Pietrzak and James Garry's answer. In the laboratory you can just make a setup using a round bottom flask, a long fractionating column connected to the condenser having a jacket to pass chilled water. Then just maintain the temperature as per the PDF given by James Garry. Initially through condensing liquid drop will be visible in the wall of the condenser which will not attach to the glass condensed which is the proof of ethanol. I the temperature will be vary, then the liquid drop will attach to the mouth which is the proof of water. So control the temperature to get the purity of ethanol.
Shuvashish
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