# What is Aqeous Tension?

1. Jun 19, 2011

### mishrashubham

Like the title says; can anyone tell me what the correct definition of aqeous tension is? How is it different from vapour pressure of water if at all it is different?

2. Jun 20, 2011

### mishrashubham

*bump*

3. Jun 20, 2011

### SpectraCat

The only thing that makes sense to me is that it would refer to the surface tension of an aqueous solution. Does that definition make sense for your application?

As to what surface tension is (in case that is your question) .. start here:http://en.wikipedia.org/wiki/Surface_tension

and feel free to come back and ask questions if anything is not clear.

4. Jun 21, 2011

### Staff: Mentor

My first idea was it is a surface tension, but I did some googling and it looks like "aqueous tension" is some obscure term related to vapor pressure. But I can't offer any details.

5. Jun 21, 2011

### Mapes

Concur; after some searching, it looks like it's an archaic term for the vapor pressure of water, as the OP suggested.

6. Jun 21, 2011

### SpectraCat

Yes, it looks like Borek and Mapes are correct .. as was the OP. I found this definition:

"Aqueous tension is the pressure exerted by the water vapor above the surface at any temperature where water and vapor are in equilibrium with each other. Hence it is called water vapor pressure. The value increases with the increase in temperature and it is equal to the atmospheric pressure at the boiling point of water. It is has to be deduced from observed pressure to know the actual pressure of the dry gas."

My suspicion is that it is an archaic term that was used before a full understanding of vapor pressure was realized, or at least standardized, and that it still persisted in usage even after it was obsolete (kind of like kcal ). Anyway, http://books.google.com/books?id=cQ...6AEwCQ#v=onepage&q="aqueous tension"&f=false" shows its usage in context in a JACS paper from 1922.

Last edited by a moderator: Apr 26, 2017
7. Jun 21, 2011

### mishrashubham

So it is after all the same thing as vapour pressure of water. Thanks to everyone for their replies.