Hot Thermo Argument
Hot Thermo Argument
(OP)
I am in a big argument over this question:
How much CO2 is released into the atmosphere when 1 gallon of gasoline is burned?
I have seen the statement in some nature magazines saying that 1 gallon of gasoline releases 20 lb of CO2 when burned.
My thought is that:
1. The gasoline weighs about 5 or 6 lbs per gallon.
2. The reaction is converting some of this mass into energy
3. The remaining mass should be less than the orginal.
Can anyone one shed some light on this? If I am wrong please explain.
jackboot
How much CO2 is released into the atmosphere when 1 gallon of gasoline is burned?
I have seen the statement in some nature magazines saying that 1 gallon of gasoline releases 20 lb of CO2 when burned.
My thought is that:
1. The gasoline weighs about 5 or 6 lbs per gallon.
2. The reaction is converting some of this mass into energy
3. The remaining mass should be less than the orginal.
Can anyone one shed some light on this? If I am wrong please explain.
jackboot





RE: Hot Thermo Argument
Cheers
Greg Locock
RE: Hot Thermo Argument
jackboot
RE: Hot Thermo Argument
RE: Hot Thermo Argument
CH2+1.5*O2=CO2+H2O
Cheers
Greg Locock
RE: Hot Thermo Argument
RE: Hot Thermo Argument
avg gasoline composition: C8H15
86.5% of the mass is C
each C combines with 2 O's, which multiplies the mass by 3.667
so 6 * 0.865 * 3.667 = 19
and
6.5 * 0.865 * 3.667 = 20.6
RE: Hot Thermo Argument
I hate being wrong, but arguing with the wrong logic can make one look foolish.
Appreciate the help.
jackboot
RE: Hot Thermo Argument
Put it another way - How many acres of forestry equate to say the CO2 produced by 100 average motor cars?
Speedy
"Tell a man there are 300 billion stars in the universe and he'll believe you. Tell him a bench has wet paint on it and he'll have to touch to be sure."
RE: Hot Thermo Argument
100 cars burn ~300gal gasoline a day
Each gallon of gasoline releases about 5.4lb of C
A tree gets 9lb heavier when it absorbs 5.4lb of C
So by this estimate, we need to grow 2700lbs of trees every day to keep up with the cars.
Since some logs float, I'm going to take a WAG and say that the density of a tree is close to that of water. A SG of 0.7, perhaps. So 2700lb of tree would translate to 1.75m^3 of solid wood. That's 3.8 trees, each with a 10" trunk, each 30ft tall. If it takes a tree only 10 years to reach those dimensions from a seed, then you only need to be growing about 14,000 trees, at various ages between 0 and 10 years old, to take up the CO2 from 100 cars. If the trees are planted on an eight foot by eight foot grid, that translates to 20.5 acres.
But don't forget - when the trees are fully mature, you can't burn them down, or let them rot, because all the CO2 would go back into the atmosphere. You have to do something with them that will keep the CO2 trapped for a very long time...
RE: Hot Thermo Argument
http://www.sciam.com
RE: Hot Thermo Argument