Voici ce qu'il manque dans ton post pour que les personne aient envie d'y répondre :


Bonjour ...

ce que tu as fait, pas fait, compris, non compris

Merci...

tu sais ce que tu fais, tu tapes sur internet, si tu ne sais pas la différence entre une combustion et une corrosion, et aprés tu as la réponse. Il faut comme même se fouler un peu moi je dis !!

Sur ce lien:

On trouve ce texte:

The zinc plating protects the steel underneath from corrosion through a patina which forms in a series of reactions. The first, the one we are all familiar with, actually happens instantly.

2Zn(s) + O2(g) -> 2ZnO(s)

In this reaction, the solid zinc reacts with atmospheric oxygen to form a thin layer of zinc oxide. Zinc oxide is a powdery white substance used in paints and sunscreen. This begins within seconds of the piece being reintroduced to air. The galvy you get already has this layer developed. It is not the dull protective patina. The following is.

ZnO + CO2 -> ZnCO3

Over a long period of time, the zinc oxide layer reacts with carbon dioxide in the air to form zinc carbonate, another white substance that dulls the surface of galvy and protects the steel very well from corrosion. While this may not look very good for maille purposes, it is extremely beneficial for industrial use where maintaining the condition of steel pieces is important far above appearance.
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Va savoir si le prof attend comme réponse le début ou la fin de ce texte.