Re: [at-l] Liquification

[bullard@northnet.org]

At 09:40 PM 9/23/99 -0400, Dave Minsek wrote:
>> At 11:57 AM 9/23/99 -0400, W F Thorneloe, MD wrote:
>> >Propane is often a problem in very cold climes, as it may
>> >liquify, and fail to become a gas.
>> 
>> Technically, I think this is incorrect, for temps down to, say, 0 deg F.
>> (Chemistry guys, help me out...)  Butane is the one that liquefies first,
>> being "thicker" than propane.  So the question arises: what is really in
>> the canisters?  Years ago, didn't those blue "Gaz" cartridges have a
>> mixture of the two compounds for some reason?
>
>Butane is heavier than propane, so it liquifies first as you cool it
>down.
>
>I took a look at my Gaz cartridge and they still do have a
>propane-butane
>mixture.  I haven't had any cold weather experience with it though. 

My MSR Rapidfire uses Isobutane (alcohol/butane?). Although I haven't used
it at low temperatures (below 45) I'm told by those who have that if you
set the canister in a container of water (admittedly a problem in winter
when all that's available is snow and ice) that the canister will not
'freeze'. The temperature of the water is irrelevant. If it's still water
it's warm enough.

Saunterer
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