Question:
I crack open my Vehicles 2nd Ed book last night, vaguely interested in
producing a main battle tank that can run on tap water.... and I see
that according to the book, a fuel electrolysis system produces 1.58
gallons of liquid hydrogen and .76 gallons of liquid oxygen per. 1
gallon of water 'cracked.'
This can't be right, can it? How can you get 2.34 gallons of stuff from
1 gallon of OTHER stuff? Is this a misprint, or is there some law of
chemical composition of which I am woefully unaware?
Answer:
- This can't be right, can it? How can you get 2.34 gallons of stuff from
1 gallon of OTHER stuff? Is this a misprint, or is there some law of
chemical composition of which I am woefully unaware? Well... 1 Gallon of water weights 8,5lbs
0,75 Gallons of LOX weight 7,296 lbs
and 1,58 Gallons of Hydrogen weight 0,9164lbs
=8,2124 lbs
as you can see the fuel electrolysis system works correct.
it isn`t volume what matters but mass,
since you konvert a liquid into two gases it shouldn´t suprise that the
resulting
volume is greater than the starting Volume -Oxygen makes up 8/9 of water's mass, and is about 10% denser
than water when it's a liquid. 8/9 of 1 gallon, reduced 10%:
.808 gallons. Pretty close to GURPS' figure. Alternately, 8/9
of the mass of 1 gallon of water is 7.56lbs while .76 gallons
of LOX (according to GURPS) is 7.3lbs. Pretty close.
Hydrogen makes up 1/9 of water's mass, and is about *1/20*
as dense as water. 1 gallon*(1/9)*20 = 2.22 gallons. Pretty
close to GURPS' figures.
In a more lengthy fashion that I wrote up first and don't
want to throw away:
