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Why does it not simply form a solid powder at the bottom of the flask?

Does silver also stick to the glass in other silver precipitating reactions?

EDIT: My question is definitely not the same as the one linked (which btw does not have an answer and is inactive for three and a half years).

Normal precipitation of silver from silver ions results in a black powder and no mirror.

As pointed in the comments, kinetics seems to play a major role here, with slow precipitation being key to achieve a mirror.

So why is it that a slow reduction of silver ions make them deposit on the surface of the glass?

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    $\begingroup$ Well, only logical explanation is that the reaction happens on surface, not in the bulk of solution, I do wonder why it happens like that, though. $\endgroup$ – Mithoron May 25 at 0:33
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    $\begingroup$ This has some information: compoundchem.com/2017/09/06/silver-mirror. Stannous chloride solution is also commonly mentioned as a preparation step: the glass surface is rinsed with this reducing agent. $\endgroup$ – Ed V May 25 at 1:41
  • $\begingroup$ @EdV The important hint in there might be that the diammine complex is more stable than the aqua complex, and leaving out the ammonia does lead to a black suspension. $\endgroup$ – Karl May 25 at 7:17
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    $\begingroup$ @Karl I agree: it was the lower right corner that had a little tidbit of maybe helpful insight. There is certainly no problem making silver nanoparticles or growing a silver tree: I have done these as demos. And adding zinc metal to a silver nitrate or nitrite solution just makes silver powder. So there must be something about kinetically hindering the process to ensure slow and orderly deposition. I hope someone provides a correct answer for this one! $\endgroup$ – Ed V May 25 at 12:42
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    $\begingroup$ @EdV Me too! But I guess someone has to write a new question that already clears the more obvious points. OP: Please update, then we can vote to reopen! $\endgroup$ – Karl May 25 at 19:59