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Question:

aluminum foil with little holes??

tonight i made tomato sauce, and transferred it to a metal bowl, covered it with aluminum foil, and put it in the fridge.... 2 hours later, i went back to look at it, and it was still hot...and there are tiny little holes, eaten away on the foil! so i immediately took it out of the metal bowl, and put it in a plastic one.. and i have it sitting on the counter. what the hell caused the little holes?? did the sauce eat away at the aluminum??

Answer:

As previously mentioned, use a glass bowl. The metal keeps the sauce heated up whilst putting it in a plastic bowl may cause the bowl to melt. The holes were most likely from the heat eating throught the aluminum foil. They could also have been made by the hot air mixing with the cold air causing 'mini-explosions' within the consealment. I hope this answers your question
Reduce the salt. Use a glass bowl (not metal, not plastic) ... The pitting potential Up is an important characteristic of every pitting system. It separates the region of passivity where the metal is practically immune from the region of heavy localized corrosion attack. On the basis of our own experimental results on pitting corrosion in the aluminum/halide-system, the present paper rediscusses fundamental questions concerning the pitting potential and the pitting process in general. At or above Up, pitting of pure aluminum in chloride solutions is the result of the combined action of single, short-life tunnelling events, which themselves propagate discontinuously. The same type of attack, to a minor extent, also occurs down to potential values 300 mV below Up. Therefore, the pitting potential is neither a lower limit for pit nucleation nor for pit growth, but appears to be the threshold value where the inactivation of tunnels is just balanced by tunnel nucleation. Taking the direct halogenation of the aluminum surface as the decisive step involved in tunnel nucleation, the pitting potential is given by the sum of the equilibrium potential of the aluminum/aluminum halide-electrode and the overpotential necessary for an appropriate nucleation rate to gurantee stable pitting. This pitting overvoltage has been evaluated, using the nucleation concept by Volmer, to calculate tunnel nucleation rate and experimental results on the life time of single tunnels. Values of the pitting potential calculated on this basis agree well with experimental results in chloride-, bromide-and iodide solutions. Only the case of fluoride pitting is different.
there's acid in the tomato juice; use saran wrap for things like that.

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