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Re: Re:Partial pressure of O2, CO2, etc., in Thailand cave

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In article <phs2tm$n6k$1@dont-email.me>, Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> writes:
> cornelius@eisner.decus.org (George Cornelius) Wrote in message:
 
>> I am here ignoring the partial pressure of CO2. Of course it
>> will  be going up as O2 is consumed by the humans in the cavity,
>> but since some of the waste product of energy production in the
>> body is H2O, there should be a smaller volume of CO2 produced
>> than O2 consumed, say, roughly, 2:1.
 
> The major metabolic source of energy - oxidation of glucose - has
>  the total chemical reaction as
> C6H12O6(glucose) + 6 O2 --> 
> 6 H2O + 6 CO2., Therefore 1:1

Thank you.  I had completely forgotten that sugars have
a large number of oxygen atoms.  Don't recall ever
memorizing the chemical formula for glucose although I
at one time could tell you one of the others - I suppose
sucrose.
 
> For fat, it can be  simplified by ommiting the minor glycerol
>  ester part as just
> 2 (CH2)n + 3n O2 --> 2n CO2 + 2n H2O, 
> so 3:2.
> 
> Large portion of CO2 will be dissolving in water, some small part
>  of it dissolving the limestone
> CO2 + H2O + CaCO3 --> Ca(HCO3)2

Yes, I had long since forgotten the reaction that transforms
aqueous CO2 and CaCO3 into limestone, but I knew it existed.
And I did expect at least some of the CO2 to dissolve in water.

In any case, the outcome is similar to what I proposed, that O2
relative percentages decrease while CO2 changes are not as significant,
and this is good because the feeling of suffocation you get in
confined spaces is apparently due to excess CO2 and not the
lack of oxygen.
 
> The relative  humidity will be close to 100%, absolute  humidity
>  in g/me will be near constant as well as temperature. Excessive
>  water vapour  will eventually condense.

My assumption as well.

> The eventual pressure decrease due decrease of total amount of
>  gasses will be mostly eliminated by sucking air via limestone 
>  porosity  and sucking water to decrease volume and increase
>  pressure. These effects lead to both absolute and partial
>  pressure increase of air gasses but CO2, which partial pressure
>  increase will be much smaller.

OK, so porosity effects do apply.  As the monsoon season
progesses is it possible the limestone becomes closer to
being saturated with water and less capable of bearing
oxygen and other gases?
 
> 1 % of CO2 reportedly start causing breathing problem, as
>  increased CO level on blood trigger response of hypothalamus  to
>  intensify breathing to get rid of it .
> 10 % has already an anaesthetic effect. ( Quotes Q&A source )
> 
> The questing remains, what was the initial  oxygen concentration
>  before flooding. Even if the internal  space was directly
>  connected to open air, the cave system  is long enough to differ
>  from average air concentration. E.g oxygen can be spent by
>  oxidation of iron and manganese minerals and by cave life
>  forms.

Difficult to know unless someone has studied it in the past
or someone is routinely recording such things over time.  And
I doubt if the divers, upon arriving initially, might have
both collected an air sample and measured absolute air
pressure.

I have heard that there were later readings after the reported
15% O2 number and that it has climbed back up to 17%.  Perhaps
there has been some oxygen replenishment. Plus, despite
indications that attempts to run an oxygen line to the
cavern had been abandoned, there are reports that there
was at least some oxygen transferred, presumably not by
carrying in oxygen tanks, in the last few days.

George
 
> -- 
> Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)
> 
> "Humour is the only effective weapon against stupidity."
> Miloš Forman
> 
> 
> ----Android NewsGroup Reader----
> http://usenet.sinaapp.com/

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Partial pressure of O2, CO2, etc., in Thailand cave cornelius@eisner.decus.org (George Cornelius) - 2018-07-07 20:55 -0400
  Re: Partial pressure of O2, CO2, etc., in Thailand cave cornelius@eisner.decus.org (George Cornelius) - 2018-07-07 21:30 -0400
  Re: Partial pressure of O2, CO2, etc., in Thailand cave cornelius@eisner.decus.org (George Cornelius) - 2018-07-07 22:19 -0400
  Re:Partial pressure of O2, CO2, etc., in Thailand cave Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-07-08 06:11 +0200
    Re: Re:Partial pressure of O2, CO2, etc., in Thailand cave cornelius@eisner.decus.org (George Cornelius) - 2018-07-08 01:14 -0400
      Re: Re:Partial pressure of O2, CO2, etc., in Thailand cave Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-07-08 07:30 +0200
        Re: Re:Partial pressure of O2, CO2, etc., in Thailand cave cornelius@eisner.decus.org (George Cornelius) - 2018-07-09 02:40 -0400

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