2
$\begingroup$

Kerosene is a blend of hydrocarbons, so it doesn't have one chemical formula. But I'd like to find an (approximate) empirical formula giving the ratios carbon and hydrogen.

I haven't found anything online, and beggars can't be choosers. My actual interest is in RP-1. There is a NIST document (archive) on its thermophysical properties which gives a spectroscopic breakdown on pages 29–32 showing that even this highly refined kerosene is mind-bogglingly complex chemically.

$\endgroup$
3
$\begingroup$

On p. 28 of the NIST document linked in the question, there is a surrogate mixture formulation of 14 hydrocarbons which closely approximates RP-1. Its empirical formula is $\mathrm {C_{11.8}H_{23.0}}$, and this should be close enough for any sort of kerosene. The properties of this surrogate are given on p. 7.

This means that burning $\pu {1 kg}$ of kerosene in air produces about $\pu {3.15 kg}$ of $\ce {CO2}$ and $\pu {1.26 kg}$ of $\ce {H2O}$ with the extra mass, $\pu {3.41 kg}$, coming from oxygen. Alternately, if you have $\pu {1 kg}$ of a perfect stoichiometric mix of RP-1 and liquid oxygen, burning it would produce $\pu {715 g}$ of $\ce {CO2}$ and $\pu {285 g}$ of $\ce {H2O}$.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.