In watercar@yahoogroups.com, "oneandonlysmack"wrote:
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> Google the definition of a mole. This will explain to you fully what is meant. You can compare molecular weights as they are based on a specific number of molecules/atoms - 6.022 x 10exp(23) regardless of the phase of the substance. I did not use molar calcs.
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> You can do the proper phase conversions. Liquid to liquid, or gas to gas at STP. You cant compare equal volumes of gas to liquid, liquid to solid, or gas to solid. You must compare equal volumes in their comparable phases. If you go back and perform the calculation correctly, you will find your results are vastly different.
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> Smack
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I disagree.
It is really quite elementary.
87 Octane Gasoline 32.0 MJ/Kg
Hydrogen 121MJ/Kg
An energy per weight comparison.
If you vaporize 1 Kg of gasoline you get 32 MJ of energy.
If you liquefy 1 Kg of Hydrogen you get 121 MJ of energy.
32/121 = .26
.26 x 1Kg = .26 Kg
According to the above calculation Hydrogen by weight has almost 4 times the energy of gasoline.
Therefore only .26 Kg of Hydrogen, liquid or gas is required to replace 1 Kg of gasoline.
You can forget Avogadro's Number, moles, and phase change.
Weight and the energy per Kg is the only criteria for comparison of Hydrogen and gasoline.
Another fuel example is firewood:
The energy content of a measure of wood depends on its species[4]. For example, it can range from 15.5 to 32 million BTUs per cord.
The higher the moisture content, the more BTUs that must be used to evaporate(boil) the water in the wood before it will`burn. Dry wood delivers more BTUs for heating than green wood of the same species.
In this wood example, weight is not even mentioned; it is assumed.
You can accurately compare fuel energy of a solid to a liquid or to a gas. It does not matter.
How many Liters of HHO must you generate in order to get .26 Kg of Hydrogen?
Energy/weight is the bottom line.
BoyntonStu
P.S. In order to liquefy Hydrogen, energy is consumed for compression and IMHO it should be factored into the energy calculation.