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Sabrina Kilian wrote:
> Soybeans, which was the only usable result google gave me for "specific
> heat of oil", have a specific heat of about 1.926 to 2.912 kj/kg-K
> according to
> http://www.blackwell-synergy.com/doi/abs/10.1111/j.1745-4530.1999.tb00500.x
>
> Sugar, according to
>
http://209.85.215.104/search?q=cache:B3m5sDbitg0J:www.solexthermal.com/assets/pdf/en/SolexCS_The%2520Solex%2520Heat%2520Exchanger%2520-%2520A%2520Better%2520Way%2520to%2520Cool%2520Sugar%2520Crystals.pdf+%22specific+heat+of+sugar%22&hl=en&ct=clnk&cd=4&gl=us,
> kilo calorie is 4.185 Joules).
>
> And, for other chemicals,
> http://www.engineeringtoolbox.com/specific-heat-fluids-d_151.html is a
> good table.
All very much lower than the 4.1 for water, as Scott originally asserted.
Hmm, interesting. It must be that water cools faster because it
evapourates then...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Invisible wrote:
> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
> methane...)
I don't know about air, but that's exactly the sort of question metric
is supposed to make trivial. One degree C heats one cm of water with one
<mumble> of energy. (Calorie?)
--
Darren New / San Diego, CA, USA (PST)
"That's pretty. Where's that?"
"It's the Age of Channelwood."
"We should go there on vacation some time."
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Darren New wrote:
> Invisible wrote:
>> OOC, any idea how much energy it takes to warm up 0.25 m^2 of air from
>> methane...)
>
> I don't know about air, but that's exactly the sort of question metric
> is supposed to make trivial. One degree C heats one cm of water with one
> <mumble> of energy. (Calorie?)
(Pedantic mode: 1 cm^3 or more precisely, 1 g).
It's likely a bit more complicated with air - it expands much more
readily than water does. But no doubt it's easy to calculate.
--
The next war will determine not what is right, but what is left.
/\ /\ /\ /
/ \/ \ u e e n / \/ a w a z
>>>>>>mue### [at] nawaz org<<<<<<
anl
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Mueen Nawaz wrote:
> (Pedantic mode: 1 cm^3 or more precisely, 1 g).
Yeah. I meant to type ccm. :-)
--
Darren New / San Diego, CA, USA (PST)
"That's pretty. Where's that?"
"It's the Age of Channelwood."
"We should go there on vacation some time."
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Invisible wrote:
> All very much lower than the 4.1 for water, as Scott originally asserted.
>
> Hmm, interesting. It must be that water cools faster because it
> evapourates then...
>
It could also be because the oil and fat in cheese has a higher
temperature then the water would. Or that what water is left has a much
higher boiling point when in solution.
For added fun, compare the energy in sugar water, say 1 kg of 87% sugar
by weight, at 125 C compared to 1kg of water at the same temperature.
Candy making is fun, if sometimes painful for reasons shown above, science.
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Invisible <voi### [at] devnull> wrote:
> On the other hand, what the HELL volume of methane gas weighs 1 kg? ;-)
>
That is actually a trick question.
The mass-part is easy enough: pure Methane consists of one C-atom (at 12g/mol)
and 4 H-atoms (at 1g/mol) for a total of 16g per 22.4 liter. Thus at regular
temperatures and pressures, you need 1400 liter of methane to get 1kg of
*mass*.
However the *weight* has to take into account buoyancy. Given an atmosphere that
consist mostly of N2 (weight 28g per mol) the buoyant force on a volume of
methane will exceed its gravitational force, i.e. it has a negative weight at
any volume.
I. e. it doesn't weigh anything - it rises up.
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>
> Yes, in a vacuum. In air or with some other material contact, you need
> to include the conduction of heat too.
>
And there can be a strong difference: Once I was experimenting with
tungsten wires as an electron emitter. Under vacuum (10^-9mbar) you could
push a current of about 4 amps to get a bright yellow glow - and an
accordingly strong emission of electrons. OOC I put the same wire in air,
connected to a lab power source driving a constant current of 4 A.
Result: only a faint red glow. And when you blew air past the wire -just
a little- it would stop glowing. And since the resistivity of metals is
proportional to the temperature, you could observe the cooling also on
the voltage meter of the power source. This setup can be used to measure
gas flows, and a similar setup is actually used in mass flow controllers.
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And lo on Mon, 02 Jun 2008 11:39:11 +0100, Invisible <voi### [at] devnull> did
spake, saying:
> Stephen wrote:
>
>> You have found the fault, now all you have to do is fix it.
>> Well done.
>
> Nah, we threw that oven away. ;-)
>
> [Ever tried throwing an oven? It's ****ing heavy! And loud...]
Out of pure curiosity did the suppliers of your new oven take the old one
away for free?
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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Phil Cook wrote:
> Out of pure curiosity did the suppliers of your new oven take the old
> one away for free?
Actually no.
It's quite irritating really. I've been hearing all kinds of stories on
the news about people stealing metal. (Not to be confused with "steeling
metal".) Apparently one house had their roof stolen (?!), and a church
had their bell stolen. But *we* leave an old oven and a sink sitting on
our front lawn for a week or two and does anybody steal it? NO. In the
end we had to *pay money* for the Council to come and take it away... grr!!
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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And lo on Mon, 09 Jun 2008 11:31:45 +0100, Invisible <voi### [at] devnull> did
spake, saying:
> Phil Cook wrote:
>
>> Out of pure curiosity did the suppliers of your new oven take the old
>> one away for free?
>
> Actually no.
Was it pure gas or did it have an electric hob?
> It's quite irritating really. I've been hearing all kinds of stories on
> the news about people stealing metal. (Not to be confused with "steeling
> metal".) Apparently one house had their roof stolen (?!), and a church
> had their bell stolen. But *we* leave an old oven and a sink sitting on
> our front lawn for a week or two and does anybody steal it? NO. In the
> end we had to *pay money* for the Council to come and take it away...
> grr!!
Too hard to dismantle into useable parts for melting down.
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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