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+--- Thread: Aluminium foil to Aluminium Oxide? (/Thread-Aluminium-foil-to-Aluminium-Oxide)
Aluminium foil to Aluminium Oxide? - toyota1515 - 09-28-2022
Firstly, I want to know if the product from this is Al2O3 (Aluminium Oxide):
I took a piece of Aluminium foil and lightly crumbled it into a ball. I weighed the Al foil ball, it was 0.334g. I then torched the Al ball with propane until near destruction, the aluminium foil shrunk and changed colour to a more dull grey metallic surface. Once cooled, I weighed the now smaller and harder Al ball and the weight was 0.38g, an increase of 0.044g which I beleive is due to oxidation. Is the product aluminium oxide? Or a partial oxidation?
Secondly, what is a good 1step method to create aluminium oxide from aluminium foil with a high grade yield? I already know of the aluminium and NaOH to create aluminium hydroxide is then heat until it decomposes to aluminium oxide; < which I think is one step too many.
I appreciate any input. And thanks for reading.
RE: Aluminium foil to Aluminium Oxide? - SpbPTSml - 09-28-2022
Al2O4 is the only stable oxide around STP, so "partial oxidation" would mean having unreacted Al metal. Calculated what weight of Al2O3 you should get with 100% reaction and compare.
And that's the problem - the oxide layer does a good job at protecting the underlying metal that it's difficult to get full conversion. You'd do better finding some Al2(SO4)3 in a garden supply store and precipitating the hydroxide using NaOH, Na2CO2, NaHCO3, or even aqueous ammonia. The product will be purer as well, most metallic Al is some alloy or other.