MineMan
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Energy Density Tables/Data?
Hello All, I am looking for data on the energy density of elements when they are oxidized and flurinated. Per weight and volume, with oxygen included
(oxidizer) and excess oxygen (atmosphere). Can anyone point me to tables of this? My goal is to access the energy density of elements used in
pyrotechnics and less used elements and thier potential.
I think this would be useful for all. For example aluminum has a higher energy density per weight then zirconium, but zirconium wins when density is
taken into account... zirconium fueled rockets can achieve 30 percent more gravitational potential.
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MineMan
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Yes. I am aware of the link you provided.... it’s obly lists a few though.
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Microtek
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Purdue Propulsion data
Then just calculate the enthalpy change during the reaction and divide by the formula weight to get the energy density.
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MineMan
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Microtek. Despite this table being from a reputable source I don’t trust it. Be and O is most energetic yet it does not show it as so. It lists some
funky chemicals I can’t find too. It seems fishy. But a table like this is more or less what I am looking for!
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Microtek
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The table doesn't list beryllium oxide at all - I don't find this suspicious. If you are looking at the heats of formation for the pure elements you
should get 0 or close to it (which you do). You should look for the change in either enthalpy (from heats of formation) or Gibbs free energy.
For instance:
CH4 + 2O2 --> CO2 + 2H2O
-75 kJ/mol 0 kJ/mol -393.5 kJ/mol -241.8 kJ/mol
Enthalpy change for the reaction is then deltaHf(products) - deltaHf(reactants): -393.5 + 2*(-241.8) - (-75 + 0) = -877.1 -
(-75) = -802.1 kJ/formula weight. Since one mole of methane weighs 16 g, methane will release about 50 kJ/g (given sufficient oxygen). If you wanted
to, you could calculate free energy instead, but it would be more complicated, and not much more accurate.
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