How is gasoline made really?

What is gasoline made of?

• More specifically, from a chemical point of view. I don't want an answer like "Its derived from oil" or something along the lines of that. An answer that gets thrown around a lot it "its made of chains of hydrocarbons". That's closer to what I'm looking for, but a bit less specific. I understand that gasoline is made of isooctane or other octanes, but there's more to it than that. I would like to know what molecules gasoline is made of, and the molecular formulae for these molecules. I also understand that gasoline varies depending on the gas station, so if you could provide the answer assuming no additives that don't affect combustion (ex: cleaners, etc.) Also it would be much appreciated if you could point me towards a site listing what additives are in each station's gasoline, but not necessary. Thank you in advance, and my apologies for the wall of text.

• Answer:

  Gasoline is a mixture of hydrocarbons plus a few "additives". Depending on the limits you want to use, there may be as many as 200 or more different compounds in gasoline. It will depend on the source of the oil, how the oil has been processed, what season of the year it is, and what other goodies your particular gasoline company as tossed into the mix. It also depends on how old the gasoline is. The longer it has sat around, so to speak, the greater the likelihood that the more volatile compounds have left the liquid. Often chemistry textbook authors assume that "octane" can be a "stand-in" for gasoline. Or they erroneously say that "octane is a major component of gasoline". As it turns out there is very little octane in gasoline. The problem arises because of the "octane rating". You might be interested to read more about that. http://en.wikipedia.org/wiki/Octane_rating Here is a partial listing of the more common compounds in gasoline. Scroll to page 5. http://www.atsdr.cdc.gov/ToxProfiles/tp72-c3.pdf These guys say that there can be over 500 compounds in gasoline and provide a short list: http://www.elmhurst.edu/~chm/vchembook/515gasolinecpd.html