NetNews Usenet Archive 1992 #20/NN_1992_20.iso/spool/rec/autos/tech/12449

Text File | 1992-09-10 | 1.6 KB | 39 lines

Newsgroups: rec.autos.tech
Path: sparky!uunet!spool.mu.edu!news.nd.edu!nowaksg.chem.nd.edu!mikeb
From: [e-mail] (Michael George Buening)
Subject: Re: A/C manifold gauges question
Message-ID: <[e-mail]>
Sender: [e-mail] (USENET News System)
Organization: University of Notre Dame
References: <[e-mail]> <[e-mail]> <[e-mail]>
Date: Thu, 10 Sep 1992 16:23:39 GMT
Lines: 27

In article <[e-mail]> [e-mail] (Jurek Rakoczynski) writes:
>In article <[e-mail]>, [e-mail] (Mark Shaw) writes:

[stuff deleted for space]

>The R12 pressure (or is temperature the correct word?) in a
>non-operating system should be the same no matter what the total
>charge is, as long as there is still liquid R12 in the system.  For
>example, the pressure in a propane tank will read the same at a given
>temperature no matter how much propane is actually in the tank.

Whoa!!! What is the logic behind this statement.  I'm not sure what
you mean here but I can't make sense of this.  As many of you know from
a simple chem/phys text:              PV=nRT
where P=pressure; V=volume; n=amount of the gas (in moles); T=temp
and R= gas constant.  When you change any one of the variables,
n,T or V, you change P.  If you have more propane in a tank at the
same temp you will have more pressure.  Because this is related to
n, or the amount of propane, you can correlate pressure with concentration
if you know what the volume is.



            --Michael Buening
            internet:[e-mail]