I have seen in many publications that solvent is heated to higher temperature than its boiling. Is it correct?
Most of people are acquainted with overheating.
When wet pot is placed on hot electric plate, you hear two type of sounds : fizzing and bumping. Fizzing is sound of normal boiling and evaporation; bumping is indication of overheating. Bumping of water drops in hot oil, explosion of eggs and large pieces in microwave - it is all overheating phenomenon in everyday life.
Yes, it is true. Overheating is a problem during distillation of pure liquids (without particles and dissolved gases). Special boiling stones, microcapillar gas inlet or stirring are necessary to prevent overheating of liquids during vacuum distillation.
Yes, under higher than standard/ambient pressure, this can always be attained.
By use of pressure-boiling point nomogram http://www.sigmaaldrich.com/chemistry/solvents/learning-center/nomo-assets.html , it is possible to generate countless number of right answers like Jack M Gallup ;-)
Most of people are acquainted with overheating.
When wet pot is placed on hot electric plate, you hear two type of sounds : fizzing and bumping. Fizzing is sound of normal boiling and evaporation; bumping is indication of overheating. Bumping of water drops in hot oil, explosion of eggs and large pieces in microwave - it is all overheating phenomenon in everyday life.
We are all ignoramuses but in different fields. Are you agree?
Some things may seem primitive, but for beginners, they can serve as an excellent introduction - especially if they are working in other areas. If necessary, it is possible to raise the level of discussion. I and Anuj did so already - but beyond this discussion.
Boiling-point elevation describes the phenomenon that the boiling point of a solvent will be higher when another compound is added, i.e., a solution has a higher boiling point than a pure solvent. This happens whenever a non-volatile soluteis added to a pure solvent.
Technically if you boil water under 5 atm of pressure at ~150C still you are boiling water at it's boiling point. (100C is at standard pressure)
Fallowing the same line than Mukut Gohain, A solvent's vapor pressure will lower when a solute is added. This happens because of the displacement of solvent molecules by the solute. And as result the boiling point will increase.
Colligative properties of solutions explains the solute(s) in a solvent phenomena (boiling point elevation), and liquids (solvents) under higher than standard pressure can also attain a higher boiling point that at standard pressure. Conversely, at lower than standard pressure you can get liquids to boil at a lower temperature than at standard conditions...
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