[entrepreneur]

Hi guys,

I am working on a product prototype and in search of a chemical which is easily available and cheap too, which reacts with oxygen instantaneously to change its colour. I am not very fixed right now on colour of chemical and in what colour it changes to after reacting, but if its colourless first and then changes to red colour after reacting with oxygen then it really serves my purpose.

Thanks

[Enthalpy]

Hi entrepreneur, welcome here!

Just to understand your query better:

You want the compound to react with air as well, don't you? Air contains much oxygen, so reacting with pure oxygen but not with air would be more difficult. Do you consider gaseous oxygen?

Reactions by oxygen contact exist (and are sometimes violent), but "instantaneously" will be limited by the time oxygen takes to reach the depth of the material. Do you want a thin liquid film, a thin solid film?

More constraints? Especially compatilibity with food, or toxicity, or unreactive with other compounds...? Accepted heat production at oxygen contact?