What type of combustion occurs when there is a plentiful supply of O_2?

Jun 25, 2017

I'll say it's complete combustion.

Explanation:

For complete combustion, which is just "normal" combustion so-to-speak, is when a substance burns in the presence of oxygen (air). It's generally understood that the oxygen is present in excess.

On the contrary, incomplete combustion is when there is not enough ${\text{O}}_{2}$ to carry out complete combustion.

For complete combustion of a hydrocarbon, for example liquid propane (${\text{C"_3"H}}_{8}$), the products are always $\text{H"_2"O}$ and ${\text{CO}}_{2}$:

$\text{C"_3"H"_8 (l) + 5"O"_2 (g) rarr 3"CO"_2 (g) + 4"H"_2"O} \left(g\right)$

For incomplete combustion (deficiency of oxygen), the products are instead $\text{CO}$ and $\text{H"_2"O}$:

$\text{C"_3"H"_8 (l) + 3"O"_2 (g) rarr 2"CO" (g) + 4"H"_2"O} \left(g\right)$

Which you can see uses up less oxygen.

This process is rather undesirable, because it can also produce soot (carbon) and poisonous carbon monoxide.