Ghostly flame dances over the flask
name: Trimethyl borate produced in situ from methanol and boric acid combusts with a green flame
Combustion of trimethyl borate
Combustion of Trimethyl Borate
Trimethyl borate synthesis pt2: combustion
Flammenfarbe von Borsäuretrimethylester - flame color of trimethyl borate
Green flame trimethyl borate FIRE
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3 CH3OH + H3BO3 → B(OCH3)3 + 3 H2O
2 B(OCH3)3 + 9 O2 → B2O3 + 6 CO2 +9 H2O
2 CH3OH + 3 O2 → 2 CO2 + 4 H2O
- Preparation of trimethyl borate. It can be prepared from boric acid and methanol.
- Weigh 5-10 grams of boric acid and put it in a flask.
- Pour 50-100 ml of methanol into the flask.
- Add a few drops of concentrated sulfuric acid.
- Heat the mixture to boiling.
- Ignite the generated vapor.
- Observe the low-temperature green colored flame
Esterification is an equilibrium reaction therefore it does not proceed to completion. Thus, it is necessary to use sulfuric acid as a catalyst and a dehydrating agent. Many boron compounds burn with a spectacular green flame. The green color is due to the emission from the excited BO* intermediate species (most prominent band at 518 nm)