I believe that we have a small problem with the use of Charles Law in the
following message. Contrary to what is stated, Charles law has nothing to
do with the boiling point of a liquid. It is concerned with the volume of a
gas at different temperatures. In addition, you must use the absolute
temperature for the calculation. Water boils at 373.15 degrees Kelvin, or
100 degrees C, and freezes at 273.15 degrees Kelvin or 0 degrees C. Water
also freezes at 459.7 degrees rankine or 32 degrees fahrenheit.
As to the use of distilled water in cooling systems, it is known that
distilled water is much more corrosive than tap water. I do not know why,
it just is.
>
>To:jurrasm@genesis.torrco.com (Mark Jurras)
>From:homestay@infolearn.com.au (Syl's Sydney Homestay)
>Subject:Re: Freeze plug for MG TC
>
>Mark
>
>I think the formula you are looking for is that for Charles Law, which
>from my old physics days goes something like:
> P1V1/T1 = P2V2/T2
>
>Where P = Pressure; V = Volume and T = Temperature
>
>Given that the volume is constant, and atmospheric pressure at sea level
>is 32 psi we have for a system running at 15 psi ( which I think is pretty
>high)
>
> 32/212 = (32 + 15)/T2
>
> So T2 = 47 x 212/32 = 311 degrees F.
>
>Any advance on 311 degrees?
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