ethanol flame?

Question

When burned ethanol produces a pale blue flame
with no residue and considerable energy, making it an ideal fuel. So why does this happen?

please elaborate

Answer 1

The chemical structure of ethanol.

CH3CH2OH

There is a single C-C bond in a molecule which is very short and already contains one Oxygen atom (meaning one of the Carbon atoms is already partially oxidized). As soon as an additional Oxygen atom combines with Ethanol, the C-C bond is usually broken.

This is unlike the larger hydrocarbons in gasoline, a typical one would be n-Octane:

CH3CH2CH2CH2CH2CH2CH2CH3

This would take many Oxygen atoms to combine to break all of the C-C bonds. With sufficient Oxygen present, both fuels result in Carbon dioxide and Water.

Answer 2

Compared with conventional unleaded gasoline, ethanol is a clean burning fuel source that combusts cleanly with oxygen to form carbon dioxide and water:

C2H6O + 3 O2 → 2 CO2 + 3 H2O

It burns more completely because ethanol molecules contain oxygen; carbon monoxide emissions can be 80-90% lower than for fossil-fuelled engines. Ethanol is already being used extensively as a fuel additive, but the use of ethanol fuel alone or as part of a mix with gasoline is increasing.

With sufficient oxygen, ethanol burns clean. The pale blue flame signifies that the temperature has reached around 1400 degree Celsius, which means a large amount of energy is released.

Answer 3

Yes but it is very explosive and if it is burning u cant see it in bright sun light.

Answer 4

alcohols burn blue because that's the spectra they emit.