Thread: Ammonia and Al

I reading on a bottle of ammonia not to soak aluminum pans in it. I'd have to guess that some kind of reaction occurs, so what is it? The only thing I can guess is 2NH₃ + 2Al --> 2AlN + 3H₂...or something like that...

i once had this guy standing next to me in chem lab adding aluminium curls to nitric acid which he had forgotten to dilute - the nicest column of brown smoke i've ever seen !

don't know whether ammonia would work in a similar fashion

Originally Posted by marnixR

i once had this guy standing next to me in chem lab adding aluminium curls to nitric acid which he had forgotten to dilute - the nicest column of brown smoke i've ever seen !

don't know whether ammonia would work in a similar fashion

that's cool... thanks for the post.

I presume that the "bottle of ammonia" that you refer to was actually ammonia gas (NH₃) dissolved in water. The resulting solution is then the base ammonium hydroxide (NH₄⁺,OH^-).

My guess is that this solution could react with aluminium to form aluminium hydroxide (Al(OH)₃). So the overall effect could be to damage the finish on aluminium pans.

Yeah, he's correct. Aluminum reacts with strong basic solutions. That's why you can't use oven cleaners either on aluminum cookware or appliances.

Because aluminum hydroxide is amphoteric so aluminum can react with basic solution.NH3 solution (NH4OH) is also a basic solution but it's very weak;it disintegrates in normal temperature:NH4OH=NH3+H2O.Although it's weak,it reacts with aluminum according to this chemical equation:
NH4OH+Al=NH4AlO2+H2(balance it yourself).
Sorry because of my poor English!