2006-08-02 17:30:33 · 6 answers · asked by Aqib 2 in Science & Mathematics ➔ Chemistry
When you distill crude, at different components seperate at various temperatures. Petrol separates at low temperatures. It is a mixture of various hydrocarbons and therefore does not have one formula...
2006-08-02 17:36:50 · answer #1 · answered by Wrobinhood 3 · 0⤊ 1⤋
Good question!
Gasoline / petrol has no set formula.
It is actually a mixture of several chemicals.
I did a GC/MS run last week on 87 octane gasoline and found the following chemicals;
Octane 86.8%
Heptane 13.4%
isopropyl alcohol <1%
nitro benzene <1%
toluene <1%
Pentane and Hexane peaks were seen but not in a high enough quantity to be indexed.
The percentages come from my comparing the chem peaks to the known quantities of check standards that I also injected so I could quantify the percentages.
The check standards that I used were flourobenzene, BPFB, Dichlorobenzene-D4 and Diclorobenzene-D5.
2006-08-03 00:09:49 · answer #2 · answered by gvloh 2 · 0⤊ 0⤋
Petrol is mostly heptane C7H16, but it contains varying amounts of other hydrocarbons like pentane, hexane, octane and benzene. Some of these are branched-chain alkanes. Straight-chain alkanes consisting of a single chain of carbon atoms in a line without any branches, with H atoms hooked on, aren't very good fuels in petrol engines; they cause pre-ignition.
2006-08-02 18:07:59 · answer #3 · answered by zee_prime 6 · 0⤊ 0⤋
From pentane to octane the alkanes are highly volatile liquids. They are used as fuels in internal combustion engines, as they vaporise easily on entry into the combustion chamber without forming droplets which would impair the unifomity of the combustion. Branched-chain alkanes are preferred, as they are much less prone to premature ignition which causes knocking than their straight-chain homologues. This propensity to premature ignition is measured by the octane rating of the fuel, where 2,2,4-trimethylpentane (isooctane) has an arbitrary value of 100 and heptane has a value of zero.
Pentane: C5H12
Hexane: C6H14
Heptane: C7H16
Octane: C8H18.
2006-08-02 18:10:02 · answer #4 · answered by gp4rts 7 · 0⤊ 0⤋
If you are refering to Octane (gasoline in USA) it is C8H18, I think. it has been awhile since I learned about that. it can take many different forms with different burn characteristics.
2006-08-02 17:35:50 · answer #5 · answered by nathanael_beal 4 · 0⤊ 0⤋
It is octane (8) carbons
CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH3
or
C8H18
2006-08-02 18:27:25 · answer #6 · answered by Tony T 4 · 0⤊ 0⤋