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Comment by bjeds | Hacker News Reader

Are you saying 1 litre (about 0.71 kg) of fuel creates 2.6 kg of CO2? :-)

You're taking a bunch of `C` in the tank (AMU: 12) and 2x `O` out of the atmosphere (AMU: 16). This means the expected mass goes from 12 -> 44, or an increase of 3.6. My trusty calculator says that takes .71kg to 2.6kg.

This is just approximate, since fuel has a bunch of H and S and other crap, so it's not 100% C. But, yes, these figures are in the right ballpark.

You are correct of course. I was intending to make an alchemy joke about a particular phrasing of the parent poster (the part about creating 1 tons of "carbon"), but misread the entire message and commented on the wrong part. :-/

Now the jokes' on me.

Ah, my bad, yes obviously it creates ~1ton of CO2, not Carbon. :)

It certainly does. The O2 comes from the air and is heavier than carbon. The carbon comes from the fuel, which is its main content by weight.

1 kg of carbon from fuel + 1.75 kg of O2 from aith = 2.75 kg of CO2.

Meanwhile the hydrogen in a hydrocarbon is somewhere in the range of 1/7th of the weight, so the fact that it all goes up the exhaust pipe in the form of water doesn't really subtract all that much weight from the input.

There's more energy in the hydrogen bonds, not the carbon-carbon bonds, right? Just adds insult to injury, if you ask me.

When you mix each 1 kg of fuel with around 3 kg of O2 during combustion, why do you think that outcome is impossible?

On the surface, it seems like you're only burning fuel in an engine. People forget, or may not even know that you're burning mostly air, and the fuel is there to help burn the air. I think this was a legit question to ask, as it's going to be a common misunderstanding for a lot of people.

I think some of the replies are missing your little s/carbon/CO2 sleight of hand there :)

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