Schooyard Science #4: Getting into hot water.

More on living at Bogota's very high altitude (8,300 feet above sea level)

Next demonstration.
We ran a little experiment and boiled water.  (We did not watch it boil.)
The theory says that the lower atmospheric pressure will allow water to boil at a lower temperature (less atmospheric pressure making it easier for low energy molecules to escape the pot...another way to say "boiling";  lower temperature=less molecular kinetic energy)

Here's the result.
The water boiled at 199 F; not the 212 F that we observe at sea level.

Checking our handy copy of the steam-water equilibrium graph (Which I've been waiting to use since my last thermodynamics class in college! See diagram to the right.), we see that a temperature of 199F has its boiling pressure at about 11.45 psi, which turns out to be about 77% of the pressure at sea level.

And we remember from an earlier posting that the predicted air pressure in Bogota's altitude is 11.5 psi, 77% of the air pressure at sea level.

Hurrah! Thermodynamics is safe for another day! (Whew!)

That's it for today, kids!
You can try this at home.

#4
(On a personal note, only after about two months living at 8,600 ft. did I finally reach a point of sleeping through the night without waking up at least once feeling out of breath.  In general we don't huff and puff as we used to.  So, we've gotten used to the thin air.)