Can Small Amounts of Chemicals Lower Water's Boiling Point?

AI Thread Summary
The discussion centers on the possibility of lowering the boiling point of water through the addition of other substances. It clarifies that the boiling point is defined at one atmosphere of pressure and is influenced by the presence of other chemicals. Significant amounts of another chemical are necessary to achieve a noticeable reduction in boiling point, as small quantities yield minimal changes. For example, adding 9% benzyl alcohol only lowers the boiling point by 0.1°C, while 20% cyclohexanol results in a 2.2°C decrease. Additionally, removing ions from regular tap water could slightly lower the boiling point due to colligative properties, but this effect is dependent on the initial concentrations of those ions. Overall, the conversation highlights the complexity and limitations of altering water's boiling point effectively.
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Is there any catalyst or substance that can do this?
 
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A lot depends on what you mean by "water". Obviously you are ready to accepts some mixture - vodka is such a mixture, and it boils at much lower temperature.

That is assuming by "lowing" you meant "lowering".

So short question, so many meanings :smile:
 
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Hmmm I seem to remember that in my time the boiling point was defined as the boiling temperature of the pure liquid at one atmosphere (or sea level). But it seems to be defined as the normal boiling point now

Any fluid boils at reduced temperatures at reduced ambient pressure. That limited us from flying above 62.000 feet, then blood starts to boil.
 
I suppose the question is meant to be understood as "lower boiling point after something has been added all other things being equal". But it is as vague as a question can be.

Andre said:
Hmmm I seem to remember that in my time the boiling point was defined as the boiling temperature of the pure liquid at one atmosphere (or sea level).

I think you have just forgot that part about "normal" or "standard" - after all, boiling point was always pressure dependent :wink:
 
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As Borek wrote, is impossible to lower the BP of water without significant amounts of another chemical (so, "catalythic" amounts are excluded).
Here there are some values of BP of mixes water + other liquid:
http://en.wikipedia.org/wiki/Azeotrope_(data )

From these data you see how is difficult to lower the BP of water: if you want to use little amounts of chemicals, you could, e.g. use 9% benzyl alcohol, but the BP lowers of 0.1°C only.; or you could use cyclohexanol and you lower the BP of 2.2°C, but you have to use at at 20%...
 
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Note that many substances will not lower, but raise the boiling point; that depends on the vapor pressure of the substance.
 
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If you mean regular tap water, I would imagine that removing some of the ions (Ca2+, Mg2+, etc.) would lower the boiling temperature slightly because of colligative properties. You can do this with a Brita filter, but the boiling point depression depends on the initial concentrations of the ions in this case. I'm pretty sure this isn't what OP meant though.
 
Hmm yes it was what I thought. It would probably against conservation of energy unless for some instance energy going into boiling water was wasted by a large degree.

I suppose the question is meant to be understood as "lower boiling point after something has been added all other things being equal". But it is as vague as a question can be.

Sorry I didn't notice the title, my meaning of Lowering the boiling point of water.

As Borek wrote, is impossible to lower the BP of water without significant amounts of another chemical (so, "catalythic" amounts are excluded).
Here there are some values of BP of mixes water + other liquid:
http://en.wikipedia.org/wiki/Azeotrope_(data )

From these data you see how is difficult to lower the BP of water: if you want to use little amounts of chemicals, you could, e.g. use 9% benzyl alcohol, but the BP lowers of 0.1°C only.; or you could use cyclohexanol and you lower the BP of 2.2°C, but you have to use at at 20%...

Interesting, but it does seem that for such a large quantity only a small gain is achieved.
 
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