That's an interesting idea... but think that's reversed. https://www.reddit.com/r/chemicalreactiongifs/comments/5cw7zj/burning_pure_methanol_left_and_pure_etha

That's an interesting idea... but think that's reversed. https://www.reddit.com/r/chemicalreactiongifs/comments/5cw7zj/burning_pure_methanol_left_and_pure_ethanol_right/ https://www.reddit.com/r/chemicalreactiongifs/comments/5cw7z... You're more likely to detect metallic or other organic contaminants which are likely (moisturizers etc) in sanitizers of both sorts. Even the effect shown above only shows up in an oxygen restricted environment (like the bucket above) due to the extra O2 the ethanol carbon needs to burn clean. You won't see that if you put it in a spoon where there's plenty of air. Any other carbon/sodium compounds are likely to show up and orange/red. https://www.youtube.com/watch?v=3jfXjG9q19Y https://www.youtube.com/watch?v=3jfXjG9q19Y Even dangerous metals like Lead (Pb) are hard to detect with simple flame test and a very pure flame. https://images.app.goo.gl/k8rSHZ4QtGR57Ca47 https://images.app.goo.gl/k8rSHZ4QtGR57Ca47