CO 2 leaking thru tires



Sat, 22 Jan 2005 13:10:45 -0800, <[email protected]>,
[email protected] (Tom Keats) wrote:

> Mike Latondresse <mikelat@no_spam_shaw.ca> writes:
>
>>> I'm obviously in this over my head. So I'm just gonna
>>> bow out, head over to Duffins Donuts, and get a $3 pack
>>> of day-olds for breakfast tomorrow.
>>>

>> Tom by that time they will be 2 days old and that is waaay past their
>> best-before date.

>
>Sometimes I like 'em a li'l crunchy. Anyways, they
>were sold out by the time I got there so I came home
>empty-handed. Brunch consisted of clam chowder and
>(pink) salmon sandwiches instead.


Bryce scooped the second to last pack at about 20:40.
He left the one with crullers on top and went for the
double-chocolates. His mandate was simply, 'no cream filled', figuring
they'd not go too well with beer.
--
zk
 
Fri, 21 Jan 2005 10:10:41 -0800, <[email protected]>,
[email protected] (Tom Keats) wrote:

>> So when you return home after a CO2 refill during a training always deflate
>> your tires and use a 02 pump.

>
>It seems to me that plain, ordinary air as would be typically
>pumped into an inner tube is a mixture of several gases, mostly
>molecular nitrogen gas (N2).


If those silly inflators were filled with N2O, I'd carry one and lots
of spare cartridges.
--
zk
 
Fri, 21 Jan 2005 10:10:41 -0800, <[email protected]>,
[email protected] (Tom Keats) wrote:

>> So when you return home after a CO2 refill during a training always deflate
>> your tires and use a 02 pump.

>
>It seems to me that plain, ordinary air as would be typically
>pumped into an inner tube is a mixture of several gases, mostly
>molecular nitrogen gas (N2).


If those silly inflators were filled with N2O, I'd carry one and lots
of spare cartridges.
--
zk
 
"Bill Baka" <[email protected]> wrote in message
news:[email protected]...
> Tom Keats wrote:
> > In article <[email protected]>,
> > "Fred Hall" <[email protected]> writes:
> >
> >
> >>CO2 is NOT smaller than O2 for crying out loud...where do you get that

from?
> >
> >
> > I consider the possibility that it may be.
> >
> >
> >>How does ADDING a carbon atom make the group of 1 carbon and 2 oxygen

atoms
> >>smaller than just 2 oxygen atoms?

> >
> >
> > Perhaps the type of bonding between component atoms has
> > something to do with it? I forget most of the chemistry
> > I ever learned, though. But maybe a CO2 molecule is bound
> > by electron sharing, and maybe an O2 molecule is covalently
> > bound, and maybe the latter type of bonding occupies more
> > space than the former? But I dunno for sure, and I don't
> > really feel like looking it up right now. But I'm not gonna
> > bet on a 3-atom molecule taking up more space than a 2-atom
> > one, just because it has more atoms in it.

>
> Yeah, I don't have my old chemistry book either and same goes for me
> about forgetting more than I remember. Maybe the Carbon molecule just
> bonds really tight with the two Oxygens. College was sooo long ago.
> >
> > Anyhow, I suspect an inner tube filled with plain air lets
> > gas molecules seep through less than one filled with a
> > single gas because the variety of diverse molecules (and
> > perhaps some somewhat larger particulates) in ordinary air
> > might tend to 'log jam' up against the wall of the inner
> > tube better than the consistently sized/shaped molecules
> > of a single gas. I'm not certain about that, though; I'm
> > just guessing.

>
> I would be also, since in plain old air the CO2 is an insignificant
> amount compared to the 80% Nitrogen and 19.9% Oxygen. Everything else is
> pretty much a trace element, with enough CO2 for plants to survive and
> some water vapor.
> >
> >
> >
> > cheers,
> > Tom
> >

> Now I may be hunting for my College Chemistry book.
> Bill Baka


Did some Googling...

On this site http://www.newton.dep.anl.gov/askasci/chem00/chem00213.htm
someone asked which is bigger a water molecule or an oil molecule...not
quite what we're after, but the answer discusses the relative size of carbon
and oxygen atoms (relatively the same):

" Water molecules consist of three atoms (two hydrogens and one oxygen).
Molecules in crude oil come in many sizes since they aren't all the same
molecule but they are all larger than water molecules. In general they
consist of many (greater than 4) carbon atoms with roughly twice as many
hydrogen atoms. There is not much difference in size between a carbon atom
and an oxygen atom so many carbon atoms (in a generic molecule of crude
oil) are definitely larger than a single oxygen atom (in a water molecule)."

so I would infer that a CO2 molecule is bigger than O2 alone.
 
In article <[email protected]>,
Zoot Katz <[email protected]> writes:
> Fri, 21 Jan 2005 10:10:41 -0800, <[email protected]>,
> [email protected] (Tom Keats) wrote:
>
>>> So when you return home after a CO2 refill during a training always deflate
>>> your tires and use a 02 pump.

>>
>>It seems to me that plain, ordinary air as would be typically
>>pumped into an inner tube is a mixture of several gases, mostly
>>molecular nitrogen gas (N2).

>
> If those silly inflators were filled with N2O, I'd carry one and lots
> of spare cartridges.


They might even be useful for putting chasing dogs in a better mood.


cheers,
Tom

--
-- Nothing is safe from me.
Above address is just a spam midden.
I'm really at: tkeats [curlicue] vcn [point] bc [point] ca
 
That is most interesting.
Has anyone timed how long a tire/tube takes to lose pressure using air
versus CO2?
Air is a mixture of a number of different atoms, we have nitrogen, oxygen
(if I rememeber only 16% oxygen in air), Co2, carbon-monoxide, and other
poluutants and stuff.
Pure Co2 like from the cartridges would not have all this extra stuff in it.
Since air is mostly nitrogen a nitrogen atom is smaller than a CO2 molecule
of carbon dioxide, thus it just doesn't seem right that CO2 would leak out
faster than nitrogen would.

"Jørn Dahl-Stamnes" <[email protected]> wrote in message
news:[email protected]...
> Earl Bollinger wrote:
>
>> How can you tell?
>> I am always pumping up my tires, they always are down a little before a
>> ride.
>> If I have to let it sit for too long they get really low or flat even.
>>
>> "marco007esq" <[email protected]> wrote in message
>> news:[email protected]...
>>> Is this true? Co2 leaks through tires? I've never heard that before.
>>>
>>>
>>> Any gurus wanna confirm or deny? What, is a Co2 molecule smaller than
>>> an O2 molecule? Huh? Any alpha-geeks wanna tell me how this is
>>> possible. (Alpha Geek is a term of respect, not derision)

>
> I have tried it. It does. It take a few days before your tire looks as it
> had another flat...
>
> --
> Jørn Dahl-Stamnes
> http://www.dahl-stamnes.net/dahls/index.php
 
On Fri, 21 Jan 2005 22:48:35 -0800, [email protected] (Tom Keats)
wrote:

>In article <[email protected]>,
> "Fred Hall" <[email protected]> writes:
>
>> CO2 is NOT smaller than O2 for crying out loud...where do you get that from?

>
>I consider the possibility that it may be.
>
>> How does ADDING a carbon atom make the group of 1 carbon and 2 oxygen atoms
>> smaller than just 2 oxygen atoms?

>
>Perhaps the type of bonding between component atoms has
>something to do with it? I forget most of the chemistry
>I ever learned, though. But maybe a CO2 molecule is bound
>by electron sharing, and maybe an O2 molecule is covalently
>bound, and maybe the latter type of bonding occupies more
>space than the former? But I dunno for sure, and I don't
>really feel like looking it up right now. But I'm not gonna
>bet on a 3-atom molecule taking up more space than a 2-atom
>one, just because it has more atoms in it.
>
>Anyhow, I suspect an inner tube filled with plain air lets
>gas molecules seep through less than one filled with a
>single gas because the variety of diverse molecules (and
>perhaps some somewhat larger particulates) in ordinary air
>might tend to 'log jam' up against the wall of the inner
>tube better than the consistently sized/shaped molecules
>of a single gas. I'm not certain about that, though; I'm
>just guessing.
>
>
>
>cheers,
> Tom


Pulling this off the top of my head, (and from the models that I
played with at the New York Hall of Science a few years back) O2 is
double-bounded, two bonds connect the two atoms. Very tight. CO2 has
the carbon in the middle with each oxygen atom off to the side forming
an angle close to 120 degrees. No way is a CO2 molecule smaller than
O2. However, as someone else pointed out, air is mostly nitrogen
anyway, and that is dense stuff. After all, the CO2 gets way up in the
atmosphere where it is destroying the O3 (ozone) layer. I have no idea
how ozone is ... oh, here's the answer:
http://www.newton.dep.anl.gov/askasci/chem03/chem03464.htm

I wonder what it means.

Well, since we're dealing with CO2 vs Air (and not O2), all that
remains to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED
AIR!!!
 
In article <[email protected]>,
dgk <[email protected]> writes:

> However, as someone else pointed out, air is mostly nitrogen
> anyway


Actually, that was me.

> Well, since we're dealing with CO2 vs Air (and not O2), all that
> remains to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED
> AIR!!!


Good question.


cheers,
Tom

--
-- Nothing is safe from me.
Above address is just a spam midden.
I'm really at: tkeats [curlicue] vcn [point] bc [point] ca
 
On Sun, 23 Jan 2005 04:16:27 +0000, dgk wrote:

> After all, the CO2 gets way up in the
> atmosphere where it is destroying the O3 (ozone) layer.


No, it's not CO2 that is destroying the ozone layer, but freon and other
chlorofluorocarbons. CO2 as a pollutant is a different issue; it
contributes to global warming because it absorbes infrared light, rather
than letting it radiate into space.

> Well, since we're dealing with CO2 vs Air (and not O2), all that remains
> to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED AIR!!!


Probably because it's easier to compress down to a liquid in order to
charge the cartridges. Also, compressed nitrogen and oxygen have other
uses; CO2 has fewer applications, maybe.

--

David L. Johnson

__o | Arguing with an engineer is like mud wrestling with a pig... You
_`\(,_ | soon find out the pig likes it!
(_)/ (_) |
 
dgk wrote:
> On Fri, 21 Jan 2005 22:48:35 -0800, [email protected] (Tom Keats)
> wrote:
>
>
>>In article <[email protected]>,
>> "Fred Hall" <[email protected]> writes:
>>
>>
>>>CO2 is NOT smaller than O2 for crying out loud...where do you get that from?

>>
>>I consider the possibility that it may be.
>>
>>
>>>How does ADDING a carbon atom make the group of 1 carbon and 2 oxygen atoms
>>>smaller than just 2 oxygen atoms?

>>
>>Perhaps the type of bonding between component atoms has
>>something to do with it? I forget most of the chemistry
>>I ever learned, though. But maybe a CO2 molecule is bound
>>by electron sharing, and maybe an O2 molecule is covalently
>>bound, and maybe the latter type of bonding occupies more
>>space than the former? But I dunno for sure, and I don't
>>really feel like looking it up right now. But I'm not gonna
>>bet on a 3-atom molecule taking up more space than a 2-atom
>>one, just because it has more atoms in it.
>>
>>Anyhow, I suspect an inner tube filled with plain air lets
>>gas molecules seep through less than one filled with a
>>single gas because the variety of diverse molecules (and
>>perhaps some somewhat larger particulates) in ordinary air
>>might tend to 'log jam' up against the wall of the inner
>>tube better than the consistently sized/shaped molecules
>>of a single gas. I'm not certain about that, though; I'm
>>just guessing.
>>
>>
>>
>>cheers,
>> Tom

>
>
> Pulling this off the top of my head, (and from the models that I
> played with at the New York Hall of Science a few years back) O2 is
> double-bounded, two bonds connect the two atoms. Very tight. CO2 has
> the carbon in the middle with each oxygen atom off to the side forming
> an angle close to 120 degrees. No way is a CO2 molecule smaller than
> O2. However, as someone else pointed out, air is mostly nitrogen
> anyway, and that is dense stuff. After all, the CO2 gets way up in the
> atmosphere where it is destroying the O3 (ozone) layer. I have no idea
> how ozone is ... oh, here's the answer:
> http://www.newton.dep.anl.gov/askasci/chem03/chem03464.htm
>
> I wonder what it means.
>
> Well, since we're dealing with CO2 vs Air (and not O2), all that
> remains to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED
> AIR!!!
>
>
>

Your model of a CO2 molecule sounds just like the one for H2O with the
two atoms attached at about a 120 degree angle. Where there is an error,
I think, is that CO2 is actually heavier than Nitrogen, as I found out
about ten years ago exploring vertical mine shafts in the old Gold
country of California. I made up a rope with foot loops every 2 feet or
so and about 50 feet long out of an original 100 foot length. I noticed
in one of the deeper mines that as I got close to the bottom I began to
feel light headed and climbed back up about ten feet pronto. There I
stayed for about 5 minutes before I could start back up to the top. A
ranger later told me that it was very dangerous to go down in those
shafts because CO2 was heavier than Oxygen or Nitrogen and tended to
collect in the bottom of those shafts. Truth or fiction I don't know
since I have never gone down a shaft like that again.
Bill Baka
 
David L. Johnson wrote:
> On Sun, 23 Jan 2005 04:16:27 +0000, dgk wrote:
>
>
>>After all, the CO2 gets way up in the
>>atmosphere where it is destroying the O3 (ozone) layer.

>
>
> No, it's not CO2 that is destroying the ozone layer, but freon and other
> chlorofluorocarbons. CO2 as a pollutant is a different issue; it
> contributes to global warming because it absorbes infrared light, rather
> than letting it radiate into space.
>

Yeah, but if we didn't have CO2 we wouldn't have life either. We breathe
Oxygen but plants breaths CO2. Calling it a pollutant is hardly fair.
Plants convert CO2 and sunlight into more plant which is eaten by
animals which are then eaten by us, yadah, yadah. We need the stuff.
Bill Baka
>
>>Well, since we're dealing with CO2 vs Air (and not O2), all that remains
>>to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED AIR!!!

>
>
> Probably because it's easier to compress down to a liquid in order to
> charge the cartridges. Also, compressed nitrogen and oxygen have other
> uses; CO2 has fewer applications, maybe.
>
 
CO2 is heavier than air (O2 or nitrogen).
They had a TV program on the PBS channel awhile back about a volcanic area
in Africa (Kilamanjaro I think) and CO2 would collect in the pits or low
lying areas. Animals would suffocate and die trying to get to the nice green
grass or nice clear water pools. Predators and scavengers would die trying
to get to the animal carcasses.
You were very lucky, usually one deep breath and you would not have made it
up to where there was some breathable air.


"Bill Baka" <[email protected]> wrote in message
news:[email protected]...
> dgk wrote:
>> On Fri, 21 Jan 2005 22:48:35 -0800, [email protected] (Tom Keats)
>> wrote:
>>
>>
>>>In article <[email protected]>,
>>> "Fred Hall" <[email protected]> writes:
>>>
>>>
>>>>CO2 is NOT smaller than O2 for crying out loud...where do you get that
>>>>from?
>>>
>>>I consider the possibility that it may be.
>>>
>>>
>>>>How does ADDING a carbon atom make the group of 1 carbon and 2 oxygen
>>>>atoms
>>>>smaller than just 2 oxygen atoms?
>>>
>>>Perhaps the type of bonding between component atoms has
>>>something to do with it? I forget most of the chemistry
>>>I ever learned, though. But maybe a CO2 molecule is bound
>>>by electron sharing, and maybe an O2 molecule is covalently
>>>bound, and maybe the latter type of bonding occupies more
>>>space than the former? But I dunno for sure, and I don't
>>>really feel like looking it up right now. But I'm not gonna
>>>bet on a 3-atom molecule taking up more space than a 2-atom
>>>one, just because it has more atoms in it.
>>>
>>>Anyhow, I suspect an inner tube filled with plain air lets
>>>gas molecules seep through less than one filled with a
>>>single gas because the variety of diverse molecules (and
>>>perhaps some somewhat larger particulates) in ordinary air
>>>might tend to 'log jam' up against the wall of the inner
>>>tube better than the consistently sized/shaped molecules
>>>of a single gas. I'm not certain about that, though; I'm
>>>just guessing.
>>>
>>>
>>>
>>>cheers,
>>> Tom

>>
>>
>> Pulling this off the top of my head, (and from the models that I
>> played with at the New York Hall of Science a few years back) O2 is
>> double-bounded, two bonds connect the two atoms. Very tight. CO2 has
>> the carbon in the middle with each oxygen atom off to the side forming
>> an angle close to 120 degrees. No way is a CO2 molecule smaller than
>> O2. However, as someone else pointed out, air is mostly nitrogen
>> anyway, and that is dense stuff. After all, the CO2 gets way up in the
>> atmosphere where it is destroying the O3 (ozone) layer. I have no idea
>> how ozone is ... oh, here's the answer:
>> http://www.newton.dep.anl.gov/askasci/chem03/chem03464.htm
>>
>> I wonder what it means.
>>
>> Well, since we're dealing with CO2 vs Air (and not O2), all that
>> remains to be asked is, WHY AREN'T THE CARTRIDGES JUST COMPRESSED
>> AIR!!!
>>
>>
>>

> Your model of a CO2 molecule sounds just like the one for H2O with the two
> atoms attached at about a 120 degree angle. Where there is an error, I
> think, is that CO2 is actually heavier than Nitrogen, as I found out about
> ten years ago exploring vertical mine shafts in the old Gold country of
> California. I made up a rope with foot loops every 2 feet or so and about
> 50 feet long out of an original 100 foot length. I noticed in one of the
> deeper mines that as I got close to the bottom I began to feel light
> headed and climbed back up about ten feet pronto. There I stayed for about
> 5 minutes before I could start back up to the top. A ranger later told me
> that it was very dangerous to go down in those shafts because CO2 was
> heavier than Oxygen or Nitrogen and tended to collect in the bottom of
> those shafts. Truth or fiction I don't know since I have never gone down a
> shaft like that again.
> Bill Baka
 
Bill Baka wrote:

> Your model of a CO2 molecule sounds just like the one for H2O with the
> two atoms attached at about a 120 degree angle. Where there is an
> error, I think, is that CO2 is actually heavier than Nitrogen, as I
> found out about ten years ago exploring vertical mine shafts in the
> old Gold country of California. I made up a rope with foot loops
> every 2 feet or so and about 50 feet long out of an original 100 foot
> length. I noticed in one of the deeper mines that as I got close to
> the bottom I began to feel light headed and climbed back up about ten
> feet pronto. There I stayed for about 5 minutes before I could start
> back up to the top. A ranger later told me that it was very dangerous
> to go down in those shafts because CO2 was heavier than Oxygen or
> Nitrogen and tended to collect in the bottom of those shafts. Truth
> or fiction I don't know since I have never gone down a shaft like
> that again.


This is true, but if it were a real CO2 pocket you would have dropped dead.
Pure CO2 is absolutely deadly:

http://www.snopes.com/horrors/freakish/smother.asp

The lightheadedness you felt was undoubtedly due to something else.

To answer the original question, which was answered a week or two ago on this
forum -- it is not the size of the molecule, but other characteristics such as
polarity or affinity which cause CO2 to diffuse through rubber faster than air
(mostly N2).

Matt O.
 
Earl Bollinger wrote:
> CO2 is heavier than air (O2 or nitrogen).
> They had a TV program on the PBS channel awhile back about a volcanic area
> in Africa (Kilamanjaro I think) and CO2 would collect in the pits or low
> lying areas. Animals would suffocate and die trying to get to the nice green
> grass or nice clear water pools. Predators and scavengers would die trying
> to get to the animal carcasses.
> You were very lucky, usually one deep breath and you would not have made it
> up to where there was some breathable air.
>

So true. If I had gone down a little more that would have been it for
me. The mine shafts accumulate CO2 because at the bottom the is no
disturbance or the air by wind that is 50 feet or more above the bottom
of the shaft. I heard that they were being filled in not just because of
that but you may have heard that some kids in a Bronco or Blazer managed
to drive into one and got wedged in about halfway down. I forgot if they
made it or not but it brought public attention to those shafts in a
hurry. I used to explore them looking for antique leftovers, but should
have had a scuba tank. I remember from Apollo 13 that it is very
important to scrub the CO2 out of the air since it is toxic when it
reaches any significant level.
Bill Baka, lesson learned.
>>
>>Your model of a CO2 molecule sounds just like the one for H2O with the two
>>atoms attached at about a 120 degree angle. Where there is an error, I
>>think, is that CO2 is actually heavier than Nitrogen, as I found out about
>>ten years ago exploring vertical mine shafts in the old Gold country of
>>California. I made up a rope with foot loops every 2 feet or so and about
>>50 feet long out of an original 100 foot length. I noticed in one of the
>>deeper mines that as I got close to the bottom I began to feel light
>>headed and climbed back up about ten feet pronto. There I stayed for about
>>5 minutes before I could start back up to the top. A ranger later told me
>>that it was very dangerous to go down in those shafts because CO2 was
>>heavier than Oxygen or Nitrogen and tended to collect in the bottom of
>>those shafts. Truth or fiction I don't know since I have never gone down a
>>shaft like that again.
>>Bill Baka

>
>
>
 
Zoot Katz <[email protected]> wrote:

> If those silly inflators were filled with N2O, I'd carry one and
> lots of spare cartridges.


Those are readily available; they're used for making instant whipped
cream. Don't know whether they'd work for tire filling, though.

--
Ray Heindl
(remove the Xs to reply to: [email protected])
 
"Matt O'Toole" wrote: This is true, but if it were a real CO2 pocket you
would have dropped dead. Pure CO2 is absolutely deadly: (clip)
^^^^^^^^^^^^^
I usually believe Snopes, but I have my doubts in this case. Every reported
death from CO2 occurs when the oxygen in the air is displaced, and
suffocation occurs. Our bodies make CO2 and exhale it as a waste product.
It is different from CO, which can kill you even when there is still oxygen
being inhaled. The difference is that CO binds to the red blood cells,
interfering with the absorption of oxygen, and it clings tenaciously. I
wouldn't drink a beverage "carbonated" with CO--CO2 is consumed by all of
us. The reason people die in a CO2 atmosphere is that it is a colorless,
odorless gas, which does not alert the person to escape, so it can lead to
asphyxiation. The same thing would happen in a 100% nitrogen atmosphere.
 
Leo Lichtman wrote:
> "Matt O'Toole" wrote: This is true, but if it were a real CO2 pocket you
> would have dropped dead. Pure CO2 is absolutely deadly: (clip)
> ^^^^^^^^^^^^^

Absolute truth. Watch Apollo 13 and you will see that the problem was
not running out of O2 but too much CO2 hence they had to duct tape some
filters. It really happened and the movie makes a fairly big deal of it
since it was a big deal to the astronauts.

> I usually believe Snopes, but I have my doubts in this case. Every reported
> death from CO2 occurs when the oxygen in the air is displaced, and
> suffocation occurs. Our bodies make CO2 and exhale it as a waste product.
> It is different from CO, which can kill you even when there is still oxygen
> being inhaled. The difference is that CO binds to the red blood cells,
> interfering with the absorption of oxygen, and it clings tenaciously. I
> wouldn't drink a beverage "carbonated" with CO--CO2 is consumed by all of
> us. The reason people die in a CO2 atmosphere is that it is a colorless,
> odorless gas, which does not alert the person to escape, so it can lead to
> asphyxiation. The same thing would happen in a 100% nitrogen atmosphere.
>
>

Actually the CO2 messes with our ability to exhale it because the
partial pressure is too high and it builds up in our bloodstreams. You
could probably die in a 95% Oxygen environment with 5% CO2.
Just a little too much CO2 and there is not enough difference in partial
pressure to exchange the gases.
At least that is what I was taught.
Bill Baka