Thread: Surface tension of a Mixed liquid

Does anyone know how to calculate the surface tension of a mixed liquid, let's say
Ammonia-water solution, whose concentration is ruled by you.

No one knows?
Dude.....

Originally Posted by ArezList

Does anyone know how to calculate the surface tension of a mixed liquid, let's say
Ammonia-water solution, whose concentration is ruled by you.

http://www.online-tensiometer.com/ob...l_methods.html


Here is a link it is a bit vague. It is basically saying that when a bubble is first formed just under the surface. The bubble because of a very large surface area to volume. Is under the maximum pressure of the liquids tension. Like when you blow up a balloon. It gets easier and easier.

This can apparently be measured and turned into a tension reading.



Sincerely,


William McCormick

Yeah you are right.

But.....you know I wanna to calculate it thereoticaly without any measurement....will that be possible?

Originally Posted by ArezList

Yeah you are right.

But.....you know I wanna to calculate it thereoticaly without any measurement....will that be possible?

I could see that some substances although held under pressure by gravity. May have a different surface tension even though they have the same specific gravity.

So I can not see how to tell if this is so without some kind of surface test.

Even floating things on the surface could bring in all kinds of variable into it.

I had never seen the capillarity tube used like that before. I cannot say if it will show a difference between different fluids of the same specific gravity.

A strong smelling ammonia solutions specific gravity is around that of water. Maybe just 1/100th more then tap water. Of a similar volume. By actual testing.

Yet you can see ammonia listed as having a specific gravity of .6819 to one, with water as one or unity.

You have to actually check this stuff out for yourself. Just as some friendly advice. You could go insane just trying to follow it in a book or books and literature.

I used a scale to check it out.


Sincerely,


William McCormick

That's quite alot of help. thanks

and just to check : does that mean in physics if we know the density, concentration, and other physics variables, and also the chemical properties of the solution, then we still can't calculate the surface tension on papper?

Originally Posted by ArezList

That's quite alot of help. thanks

and just to check : does that mean in physics if we know the density, concentration, and other physics variables, and also the chemical properties of the solution, then we still can't calculate the surface tension on papper?

I would not rule that out.

But only because I have never tried the capillarity bubble test. To check the surface tension against the specific gravity of the fluid or fluids with the same and different specific gravities.

I was thinking about blowing up a small balloon in sand. I don't see much apparent attraction between the grains of sand. A small balloon right at the surface would probably just move the sand aside with little resistance.

Yet the density or the weight of sand, would if you tried to blow up that balloon a foot below the surface of the sand, cause great pressures.

This would be new territory for me.

Sincerely,


William McCormick

well....the same to me......