Of course the whole point is a concern about the amount of C02 being released in the atmosphere. But is this a cause for concern? A recent 20/20 with John Stossel interviewed two scientists from the Smithsonian Astrophysical Observatory. They pointed out that the earth's temperatures over the last two hundred years are lower than the median for the last few thousand years. The earth experienced the little ice age which had record cool temperatures about 1806. Since that time the earth has been gradually warming, but is still below the mean and the earth was much warmer around 800 AD. In a recent book "The Role of the Sun in Climate Change", NASA scientist Kenneth Schatten and Douglas Hoyt point out the strong correlation between the earth's temperature and solar activity. Their conclusion: "In brief , recent studies make a good case that the sun's radiant output varies over decades and longer time scales and that these variations are playing a significant role in climate change." The sun appears to be a variable star. Some other historical studies covering several thousand years using fossil and geological evidence indicate that CO2 increases as a result of global warming and is not the primary cause of it. I think much more study is necessary before making draconian political decisions based on what may be bad science. The Kyoto Accords may be premature. Clear Skies Don Colton -----Original Message----- From: utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com [mailto:utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com]On Behalf Of Josephine Grahn Sent: Saturday, August 07, 2004 4:13 PM To: Utah Astronomy Subject: RE: [Utah-astronomy] Is this right? (OT) John, Actually, the statement should have been 6 pounds of gasoline yields approximately 20 pounds of carbon dioxide. Each molecule of octane contains 8 carbons and 18 hydrogens. The atomic weight of carbon is 12, the atomic weight of hydrogen is 1. So each molecule of octane has an atomic weight of 114. In burning octane, all of the carbon goes to carbon dioxide. So for each of the eight carbons, you must take 2 oxygens (O2) from the surrounding air. The atomic weight of oxygen is 16. Therefore, if you start out with one molecule of octane, total atomic weight of 114, you create 8 molecules of carbon dioxide. Each molecule of carbon dioxide has an atomic weight of 44, and you now have 8 of them, which yields a total atomic weight of 352. 352 divided by 114 equals 3.1. 6 pounds times 3.1 equals 18.6 pounds of carbon dioxide from 6 pounds of gasoline. (Gasoline is approximately 84 to 90 % octane and 10 to 16 % heptane. The heptane is 7 carbon atoms rather than eight. This makes less than 2% difference in the final numbers.) Now, as to the gallons versus pounds of gas. I believe the original calculation was for 1 gallon of gas, which weighs approximately 6.3 pound. Either Patrick or the BBC made an error by saying gallons instead of pounds. 6.3 pounds times 3.1 would equal 19.53 pounds, and yield the rounded "twenty pounds of carbon dioxide to 1 gallon of gas". On the internet, you can find different values for the weight of gasoline, but the one that most of the people in the industry use is 6.3 pounds per gallon of gas. Sincerely, Jo Grahn At 10:10 AM 8/7/2004 -0600, you wrote:
I think there was a part of the original statement that was converted incorrectly ... The statement listed 6 GALLONS of gasoline. Then later, this was changed to 6 pounds.
I agree that from this formula the ratio is 6 lbs of octane to 18.4 lbs of CO2. But how much octane is contained in a gallon of gasoline? No matter what you do to a chemical compound, when you add up their molecular weights, they must remain the same. Yes each molecule can have different weights, but the sum of ALL components will be the same going in as going out of the process.
I believe that a gallon of gasoline weighs about 7.5 lbs (Not sure exactly), so the original statement of 6 gallons of gas would be around 45 lbs of gas. When burned, producing about 20 lbs of CO2 sounds plausible to me.
John Zeigler www.johnstelescopes.com www.mirrorkits.com
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