Question

Why do aromatic compounds give off a smoky flame?

Answer 1

Why do aromatics give off a sooty flame? Incomplete combustion!

Explanation:

We can use benzene as an example.

Its complete combustion is,

`C_6H_6 + 15/2O_2 rarr 6CO_2 + 3H_2O`

Nevertheless, because the molecule is stable and carbon dense, it might combust incompletely to give `CO` and `C`, i.e. soot.

`C_6H_6(l) + 6O_2(g) rarr 4CO_2(g) +CO(g) +C(s) + 3H_2O(g)`

How do I know that only 1 equiv of `CO` and `C` were produced? Of course, I don't know that. I do know that my equation should be balanced.