(Don Klipstein) wrote in message ...
In article , John
Michael Williams wrote:
...

I thought the ultimate energy per mass was magnesium and oxygen (or was
it beryllium and oxygen?), just a few times as much energy per mass as TNT
and not good like usual rocket propellants for producing gas to use as
rocket exhaust.

It depends on the electrochemical gradient, I think.
Hydrogen burning in fluorine probably produces more combustion
energy than anything else, per unit mass.

That one is up there, but let's check heat of formation...

HF gas: 63.991 KCal/mole, 3.19955 KCal/gram

MgO: 145.76 KCal/mole, 3.644 KCal/gram, but with no gaseous output.

Right. Agreed, although in water, HF produces 78.6 kCal/mole,
putting it ahead of MgO by mass.

The gaseous output would subtract heat energy, so if the goal was
radiant heat and not momentum, MgO would be 'way ahead.

...

John

John Michael Williams

Cecil Moore wrote in message ...
John Michael Williams wrote:
I share this skepticism. Burning TNT probably would produce 10x more
free energy than detonating it.

When you detonate it, what happens to the 90% lost energy?
Fails to actually detonate?

Based on recent postings, my "10x" might be too high,
but what would happen is that the uncombusted atoms
of the TNT would be just accelerated away by the shock
of detonation.

Eventually, they might be combusted, but not as part of
the detonation. So, their combustion energy contribution
isn't counted as part of the explosion.

John

John Michael Williams

"Cecil Moore" wrote in message
...
DarkMatter wrote:
First, tell me how one "burns TNT". It is a high explosive. I
think its "burn rate" would be pretty fast, and not manageable.

If one arranged the TNT into a fuse, how fast would it burn?
--
73, Cecil http://www.qsl.net/w5dxp

Don't know about strings of TNT but I just checked on primacord
and it detonates along it's length at greater than 6000 feet per second.

HWB

In article , DarkMatter wrote:
On Tue, 23 Mar 2004 09:50:00 -0600, Cecil Moore
Gave us:

John Michael Williams wrote:
I share this skepticism. Burning TNT probably would produce 10x more
free energy than detonating it.

When you detonate it, what happens to the 90% lost energy?
Fails to actually detonate?

First, tell me how one "burns TNT". It is a high explosive. I
think its "burn rate" would be pretty fast, and not manageable.

That guy's empty skull cavity has a lot of free space in it.

I know that TNT does not detonate easily. It may burn rather fast like
nitrocellulose or moderately like the stuff they make road flares with if
you just ignite it.

Some other high explosives are also capable of burning at moderate
rates. I have heard of C4 being somewhat usable as a fuel to heat food
with, easy to get burning without detonating.

I remmber reading in an encyclopedia that nitroglycerin can burn with a
quiet flame in a wick, but I would not try that one. They do mix a small
amount of nitroglycerin with nitrocellulose in some "smokeless powders",
and that others have just nitrocellulose.

Since TNT does not contain enough oxygen in its nitro groups for
complete combustion, burning it will get you some more energy than is
released by a detonation of it.

- Don Klipstein )

In article , John Woodgate wrote:
I read in sci.electronics.design that Don Klipstein
wrote (in ) about 'CB Radios,
Cellphones and Gasoline Vapor Ignition', on Tue, 23 Mar 2004:
That one is up there, but let's check heat of formation...

HF gas: 63.991 KCal/mole, 3.19955 KCal/gram

MgO: 145.76 KCal/mole, 3.644 KCal/gram, but with no gaseous output.

Do you have the figures for CsF?

No I don't. I expect it to be more per mole and less per gram than HF.

I do have a figure for RbF, 133.31 KCal/mole, 1.276 KCal/gram.

But another one that ranks high per gram is Al2O3.
That one gets 389..49 KCal per mole, 3.818 KCal per gram, and 2.45% more
if you get it to be corundum crystal rather than amorphous powder.

B2O3 gets 279.81 KCal per mole, 3.886 KCal per gram.

I think BeO is also up there, probably even more per gram, but I do not
have that figure. I suspect it is the champ in energy per gram of
reactants, and misremembered by one element in the same column since
MgO is not the champ after all.

DON'T TRY THIS AT HOME.(;-)

- Don Klipstein )

"noname" wrote:


"Nico Coesel" wrote in message
...

I'm pretty sure that it won't work that simple. There are other
factors at play that make controlling things with a telephone a lot
harder to achieve than you think... For everyone's safety I'm not
going into the details.

You could, only there are no details.

piezoelectric one, since with a piezo the circuit would differ slightly. A
reed relay could do the switching. Using an NPN, the circuit would look like
this: Negative ground, connected with ringer's "-", to battery "-" and
through a forward-biased shottky to the emitter. The transistor's base
connected through a 2K2 resistor to battery "+". Base also connected to
diode "+", while diode "-" is connected to ringer "+". Collector through
relay coil to battery "+", a capacitor across the relay coil. That's it. The
relay contacts can be used to switch on a lamp, connected to the same
battery and placed so that the hearing-impaired person can easily see it.
Note to hearing-impaired preople: this circuit may not always work, it
depends on the type of ringer and on the volume setting. I did not test it
with any ringers either, but I think many old-style ones should do.

Way too complicated and it still doesn't work reliably. I've used
electronic kitchen timers -which basically have the same circuitry- in
numerous devices (Eprom erasers, etching tanks, UV exposure units,
etc, etc) but this method is too unreliable for anything that needs a
100% predictive trigger.

--
Reply to nico@nctdevpuntnl (punt=.)
Bedrijven en winkels vindt U op www.adresboekje.nl

On Tue, 23 Mar 2004 16:08:06 -0000, (Dave Platt)
wrote:


It appears that burning is also a viable method of destroying TNT.
http://www.humanitarian-demining.org...tral/remic.asp
describes a method for destroying land mines "in situ" via burning.
It's a neat trick - a small shaped charge of explosive creates a
high-velocity gas jet which breaks open the (TNT-loaded) land mine,
and also delivers a charge of a pyrogenic chemical which ignites and
burns the TNT without detonating it.
Yep I have seen a documentary on TV where the cut open old WW2 bombs
(UK ones), and then simply burned the stuff in it.
That is how they get rid of the old bombs.
JP

On Tue, 23 Mar 2004 19:43:01 GMT, "Ken Fowler"
wrote:

While the thread might be interesting to some readers, and granted that the original topic had
something to do with arcing associated with antennas, the discussion of explosives is very off-topic
for rec.radio.amateur.antenna.
Only because you do not use enough output power :-)

"Don Klipstein" wrote in message
...
In article , John Woodgate wrote:
I read in sci.electronics.design that Don Klipstein
wrote (in ) about 'CB Radios,
Cellphones and Gasoline Vapor Ignition', on Tue, 23 Mar 2004:
That one is up there, but let's check heat of formation...

HF gas: 63.991 KCal/mole, 3.19955 KCal/gram

MgO: 145.76 KCal/mole, 3.644 KCal/gram, but with no gaseous output.

Do you have the figures for CsF?

No I don't. I expect it to be more per mole and less per gram than HF.

I do have a figure for RbF, 133.31 KCal/mole, 1.276 KCal/gram.

But another one that ranks high per gram is Al2O3.
That one gets 389..49 KCal per mole, 3.818 KCal per gram, and 2.45% more
if you get it to be corundum crystal rather than amorphous powder.

B2O3 gets 279.81 KCal per mole, 3.886 KCal per gram.

I think BeO is also up there, probably even more per gram, but I do not
have that figure. I suspect it is the champ in energy per gram of
reactants, and misremembered by one element in the same column since
MgO is not the champ after all.

I suspect the champ is something like a mix of liquid ozone with liquid
acetylene.
Try it and report back.

--
Dirk

The Consensus:-
The political party for the new millennium
http://www.theconsensus.org

(John Michael Williams) wrote in message . com...
(Bill Sloman) wrote in message . com...
(John Michael Williams) wrote in message . com...
...

I share this skepticism. Burning TNT probably would produce 10x more
free energy than detonating it.

Trinitrotoluene is C7H5N3O6 and would burn to 7 CO2 molecules, 2.5 H2O
molecules and 1.5 N2 molecules - for which you'd need 10.5 extra
oxygen atoms, over and above the six oxygen atoms available in the
original TNT molecule.

Being simple-minded about it, 16.5/6 is 2.75, not ten, and that
exaggerates the advantage, because burning carbon to carbon monoxide
release quite a lot more energy than burning carbon monoxide to carbon
dioxide, which is where you use up seven of your extra 10.5 oxygen
atoms.

Right, letting the N_3O_6 drop out as nitrogen dioxide,
7*CO_2 + 2.5*H_2O is just 16.5. However, detonation
might not even produce the nitrogen dioxide, and it
might lose energy by producing NO instead of dioxide.
So I'm not sure where the 6 comes from.

Detonating or burning TNT won't produce any significant amount of
nitrogen dioxide - the oxygen originally bonded to the nitrogen will
end up bonded to the hydrogen (as water) and the carbon (as carbon
monoxide). That is what the nitrate groups are there for.

Also, the energy from C+O_2 would be much lower than that
from the H_2+O, per O, I think, but I'm not sure how
well defined the combustion process is, that is being
assumed.

It is pretty well defined. The hydrogen-oxygen bond is stronger than
the carbon oxygen bond, so all the hydrogen is going to end up as
water, and the rest of the oxygen will be taken up as carbon dioxide.
The energy released by these reactions can be worked out pretty
exactly - the National Bureau of Standards publishes table of
"enthalpies" for loads of chemical compounds.

You have to fine-tune the published data to account for the
temperature and physical states of the reactants before and after the
reaction, but this is strictly detail work.

The procedures involved in making the calculations were covered in the
thermodynamics course I did in second year chemistry back in 1961. As
far as I know, all chemistry and physics graduates have to do such a
course.

I think, if detonation in air also entailed
complete combustion, then detonation would
produce the same energy as would direct combustion.

Detonation can't entail complete combustion - at least not for TNT,
where the three nitro-groups don't provide enough oxygen - in the
ratio 6 : 16.5 - for complete combustion, and atmospheric oxygen can't
diffuse into the fire-ball anything like fast enough to make up the
deficit.

As Don Klipstein has pointed out, nitroglycerin and PETN (penta
erithytol nitrate IIRR) do contain enough nitro-groups to allow more
or less complete combustion during detonation.

You mentioned something earlier about atomic hydrogen: I
am not sure about this, because combination to H_2 would
just be creation of one covalent bond. Can you explain
further?

It is "just" the creation of one covalent bond, from a situation where
there was no covalent bond. Most chemical reactions involve exchanging
one covalent bond for another - stronger - covalent bond.

The noble gases - helium, neon, argon, xenon, radon - are the only
elements that don't form strong covalent bonds. You've got to heat
most elements to astronomic temperatures before you see appreciable
populations of single atoms.

The exact amounts of energy involved are all available in the open
literature - that is where I found them, some thirty years ago, and
I'm sure that they are still available now.

-------
Bill Sloman, Nijmegen