Climate change - what can we do?

pink poodle

気が狂っている男
The VW saga wasn't about CO2 emissions, it was about NOx emissions.

1l of petrol produces 2.3kg of CO2.
How does that work? I'm not very literate in science, but...how does something get used, turned into energy, and yet produce a waste product of greater mass than the input?

If I boil 1kg of water, it isn't going to become 2litres of steam.
 

PJO

in me vL comy
How does that work? I'm not very literate in science, but...how does something get used, turned into energy, and yet produce a waste product of greater mass than the input?

If I boil 1kg of water, it isn't going to become 2litres of steam.
No but the water isn't changing into something else and reacting with other elements.

If we assume petrol is pure octane which it is not but it has a high proportion (90-98%) then 1L of petrol is 703g of octane (density of octane)

Octane has a molecular mass of 114.2 g/mol so we have 6.154 moles of octane in 1L of petrol. Each octane molecule is composed of 8 carbon atoms and 18 hydrogen atoms. So that's 49.23 moles of carbon and 110.78 moles of hydrogen.

If complete combustion occurs (which it doesn't) we would get 49.23 moles of CO2 and 55.39 moles of H2O. Converting those back to grams we have 2166g of CO2 and 997g of H2O.

591g of the 2166g of CO2 is actually carbon if we were to do it by weight.

TLDR: 2.3kg CO2 from 1L of petrol is a reasonable approximation.
 

LQQK

Likes Bikes
How does that work? I'm not very literate in science, but...how does something get used, turned into energy, and yet produce a waste product of greater mass than the input?

If I boil 1kg of water, it isn't going to become 2litres of steam.
Watch this video by John Cadogan, it explained it in a way that even I could understand.
 

pink poodle

気が狂っている男
Watch this video by John Cadogan, it explained it in a way that even I could understand.
20+ minutes of science? I'm going to need something shorter than that.

No but the water isn't changing into something else and reacting with other elements.

If we assume petrol is pure octane which it is not but it has a high proportion (90-98%) then 1L of petrol is 703g of octane (density of octane)

Octane has a molecular mass of 114.2 g/mol so we have 6.154 moles of octane in 1L of petrol. Each octane molecule is composed of 8 carbon atoms and 18 hydrogen atoms. So that's 49.23 moles of carbon and 110.78 moles of hydrogen.

If complete combustion occurs (which it doesn't) we would get 49.23 moles of CO2 and 55.39 moles of H2O. Converting those back to grams we have 2166g of CO2 and 997g of H2O.

591g of the 2166g of CO2 is actually carbon if we were to do it by weight.

TLDR: 2.3kg CO2 from 1L of petrol is a reasonable approximation.
So many words to look up...I spent most of my high school science classes being naughty. I'm not saying it doesn't or that I don't believe you folks, I'm just amazed that the mass of the waste can be more than the input.
 

The Duckmeister

Has a juicy midrange
How does that work? I'm not very literate in science, but...how does something get used, turned into energy, and yet produce a waste product of greater mass than the input?

If I boil 1kg of water, it isn't going to become 2litres of steam.
Air-fuel ratio. The exact mix varies between engine tunes, but as a general guide the air-fuel mix in a car engine is about 14:1; that is for each kg of petrol that gets burned, there are 14kg of air (which is ~78% nitrogen). That's a total combustible/reactive mass of 15kg. There's a lot of reactive stuff going on in that mix, which makes 2.3kg of CO2 out of it not at all ridiculous.
 

creaky

XMAS Plumper
How does that work? I'm not very literate in science, but...how does something get used, turned into energy, and yet produce a waste product of greater mass than the input?

If I boil 1kg of water, it isn't going to become 2litres of steam.
The petrol provides the C, the air provides the Os. C is worth 12, each O is worth 16.

So don’t blame the petrol, pure air is causing the majority of the problem.
 

pink poodle

気が狂っている男
Air-fuel ratio. The exact mix varies between engine tunes, but as a general guide the air-fuel mix in a car engine is about 14:1; that is for each kg of petrol that gets burned, there are 14kg of air (which is ~78% nitrogen). That's a total combustible/reactive mass of 15kg. There's a lot of reactive stuff going on in that mix, which makes 2.3kg of CO2 out of it not at all ridiculous.
This I kind of understand. Thank you!
 

pink poodle

気が狂っている男
The petrol provides the C, the air provides the Os. C is worth 12, each O is worth 16.

So don’t blame the petrol, pure air is causing the majority of the problem.
Fuck oxygen. Let's get rid of it and put and to the global warming!
 

Dales Cannon

lightbrain about 4pm
Staff member
Fuck oxygen. Let's get rid of it and put and to the global warming!
There are some pilot fossil fuel plant that burn pure O2 instead of air. One right here in Hong Kong. Idea is to get rid of NOx, SOx and pox to allow sequestration of the CO2 produced.
 

pink poodle

気が狂っている男
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