Nick -
I think Bruce just gave a good calibration on this with his great
description not only of why or why not to breathe Uranium Hexaflouride
(cuz you will have to stand on your head to empty it from your lungs!)
but also the relative density of the gasses in question.
Try the analogy of mixed drinks. Every good bartender knows that you
put the alcohol into the glass first so that when you add the
water-based stuff (tonic, seltzer, juice, etc.) the two mix naturally.
If you pour the alcohol *over* the watery things, you risk the alcohol
"floating" rather than mixing. We could go into the implications of low
and high "proof" alcohol, etc.
But are you surprised that your bottle of wine, beer, or hard liquor
hasn't seperated before you even get to pour it?
AS I think Doug mentioned, thermal energy alone is a good mixer... even
without the constant stirring of wind and convection...
- Steve
Sorry. Mixed up the weight of N and O. So my question should have
been, Why don't we wake up in a layer of oxygen on still nights?
Which brings us to your question about what would make me expect that
a mixture would separate out into its lighter and heavier components.
You tell me! Other things being equal, don't heavier things tend to
sink when mixed with lighter ones?
N
*From:*friam-boun...@redfish.com [mailto:friam-boun...@redfish.com]
*On Behalf Of *Douglas Roberts
*Sent:* Tuesday, June 12, 2012 2:43 PM
*To:* The Friday Morning Applied Complexity Coffee Group
*Subject:* Re: [FRIAM] atmospherics
Let's not ignore temperature: my farts are a good 20 degrees F above
ambient (at present), and tend to rise before mixing into the
unfortunate nearby environs. And, just in case you were wondering
what the composition of a fart was:
The major components of the flatus, which are odorless, by percentage
are:^[4] <http://en.wikipedia.org/wiki/Flatulence#cite_note-3>
§Nitrogen <http://en.wikipedia.org/wiki/Nitrogen>: 20--90%
§Hydrogen <http://en.wikipedia.org/wiki/Hydrogen>: 0--50%
§Carbon dioxide <http://en.wikipedia.org/wiki/Carbon_dioxide>: 10--30%
§Oxygen <http://en.wikipedia.org/wiki/Oxygen>: 0--10%
§Methane <http://en.wikipedia.org/wiki/Methane>: 0--10%
*4. ^ <http://en.wikipedia.org/wiki/Flatulence#cite_ref-3>*"Human
Digestive System"
<http://www.britannica.com/eb/article-45361/human-digestive-system#294193.hook>.
/Encyclopædia Britannica/. Retrieved 2007-08-22.
--Doug
On Tue, Jun 12, 2012 at 12:33 PM, Roger Critchlow <r...@elf.org
<mailto:r...@elf.org>> wrote:
Nick --
N2 weighs 28 gm/mole, O2 weighs 32 gm/mole, Ar weighs 40 gm/mole, CO2
weighs 44 gm/mole, and H2O weighs 18 gm/mole.
Why would anyone expect the lighter components of a mixture to fall
down more than the heavier ones? If anything, you'd expect the
heavier ones to concentrate toward the bottom.
And why would anyone expect a mixture to spontaneously separate into
pure components? That happens in real life like where?
As it happens, CO2 is the heaviest normal component and it does pool
in confined spaces often enough that CO2 alarms are available in
hardware stores. Propane, C3H8, weighs 44 gm/mole and is notorious
for pooling in confined spaces and then exploding, often in the bilge
of a boat and spectacularly.
-- rec --
On Tue, Jun 12, 2012 at 10:44 AM, Nicholas Thompson
<nickthomp...@earthlink.net <mailto:nickthomp...@earthlink.net>> wrote:
So, somebody asked me, in my role as a weather nerd, how come the
nitrogen in the atmosphere doesn't all fall to the bottom on still
nights and suffocate us all. I asked the question of
stupid-answers-to-stupid-questions-asked-by-stupid-people.com
<http://stupid-answers-to-stupid-questions-asked-by-stupid-people.com>
and THEY said, well, there's just too much going on. N molecules
and the O molecules are just too busy, what with convection and
windcurrents, and all, to separate, even on still nights. Now,
that business doesn't prevent cold molecules of Nitrogen and
Oxygen to separate from warm ones, or wet ones (not sure what
that means) to separate from dry ones. I was hoping that somebody
on FRIAM could give some sort of a clue what kind of a mixture AIR
is? It is suddenly seeming kinda special.
Nicholas S. Thompson
Emeritus Professor of Psychology and Biology
Clark University
http://home.earthlink.net/~nickthompson/naturaldesigns/
<http://home.earthlink.net/%7Enickthompson/naturaldesigns/>
http://www.cusf.org <http://www.cusf.org/>
============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org
============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org
