I'm curious if cars release carbon dioxide into the atmosphere?

[Isomer]

I know they release nitrates, but do cars also release carbon dioxide? Or is it carbon monoxide? I really don't know much about vehicle emmisions, but I was watching a documentary about it, and now I'm curious!!!

[silkworm]

It's generally a mix of carbon monoxide and dioxide, because of the ineffeciency of the combustion engine.

 

It is true that NOx and sulfates are released as well, but those are due to impurities. Basically, burning requires organic material and the ideal product is carbon dioxide, but a lot of carbon monoxide will show up as well usually, depending on the efficiency of the process and how clean it is.

 

So burning any organic material, including fossil fuels, releases carbon dioxide. That energy comes generally from the creation of carbon dioxide and water.

[Klaynos]

Catalytic conveters, convert some of the carbon monoxide into carbon dioxide, to make it less toxic for humans...

 

http://en.wikipedia.org/wiki/Catalytic_converters

[insane_alien]

i thought the nitrates came from nitrogen in the air that was forced to react by the spark plug. or am i just blathering?

[ed84c]

Under the high temperatures in the combusting chamber is my understanding of it.

[DrCloud]

...do cars also release carbon dioxide?

 

Yes. Everyone here is pretty well on track, but there's considerable imprecision in the language. For example, they don't really "release" CO2; they create it in the combustion process and it flows out the tailpipe. As noted, because the combustion is imperfect, they also create and emit CO as well as (due to the high pressures & temperatures in the cylinders) oxides of nitrogen, NOx (x=1,2, mostly).

 

"Burning" things (or "combusting" them) oxidizes them, so burning molecules containing carbon oxidizes the carbon into CO2; because the complex hydrocarbons in gasoline also contain hydrogen, cars also create and emit water vapor. Ideally, that's all they'd emit, but with the imperfections in the process, there's the other stuff, too.

 

Vehicles, generally, emit something in the vicinity of 20% of all the CO2 that gets put into the atmosphere via activities involving humans (I don't remember the exact figure; it could be as high as 30%). Power plants big contributors, too, as are wood/coal fires in developing countries. HPH