On Friday 20 November 2009, Andy Pugh wrote: >2009/11/20 Gene Heskett <gene.hesk...@gmail.com>: >> A cube of dry ice sitting on >> it would help, but would raise the available oxygen too. > >I am fairly sure it would displace the oxygen (being heavier) and so >would both cool and reduce oxide formation.
That would depend on how easy it would be to obtain some oxygen from the co2 vapors. How active is carbon dioxide compared to say sulfur dioxide? Sulfur dioxide is a very unstable gas, but its chemical reaction is the opposite as it will grab, by force, an oxygen molecule from any available src in its quest to convert itself to sulfur tri-oxide, which as some of us know it just another name for sulfuric acid. This is why a leaking so2 refrigerant system (commonly used in household refrigerators back in the late 30 and mid-40's) is so deadly, the gas will steal the oxygen from the moisture in your lungs to make sulfuric acid and _that_ burns your lungs out. In the gas fired camper fridges, that is also the destruction mechanism for those as even one molecule of water sealed into that system will, over time, generate enough sulfuric acid to eat a hole in a thin spot someplace. I don't believe you will ever see a 'Dometic" made unit that will ever have more than a 5 year warranty on its no moving parts refrigeration system for exactly that reason. And if its gas fired, it IS a Dometic inside the brand name labels & has been so since the 1950's after Servel disappeared. Today I think 12 volt versions of the little bitty fridges like wally sells for a bit over a hundred dollar bill have replaced those gas fired ones in 100% of the new weekend campers. I have one in the basement that I carry with me when I'm going to be on the job someplace for more than 3 or 4 days. But it runs on wall power. As for how active the carbon dioxide from the dry ice is, can it be broken down to supply the o in its o2? I am not _that_ much of a chemist, hence the question. :( >You might have hit on a cunning plan, and it would look cool too. I agree, but the expense of keeping one supplied with dry ice would also have to be a factor. Locally, I believe its special order and several dollars a pound, weight measured at their end of the shipping of course. ;) -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. <https://www.nrahq.org/nrabonus/accept-membership.asp> There's no saint like a reformed sinner. ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
