Diamond vs. Acids at room temperature

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Can someone explain to me why at room temperature acids cannot dissolve diamond? Is it related to its hardness?
 
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Vanadium 50 said:
To help focus the answer, why do you think they should?
What do you mean?
 
PatrickP2 said:
What do you mean?

Well, for one thing, do acids dissolve the glass bottles that they are stored in? :wink:
 
I read once that hydrofluoric acid can dissolve glass, whereas it does not react with diamond. I am curious why this is the case? Is it because the carbon atoms are so close together?
 
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Vanadium 50 said:
Hydrofluoric is a weak acid. It's about as strong as vinegar.

Why bring it up?
The reason I mention this is that the acid is capable of dissolving glass.

[Mild insult removed by the Mentors]
 
symbolipoint said:
Diamond is a very different chemical than most "glass".
In fairness to the OP, I'm the one who brought up glass.
 
There are no good protonation sites in the diamond lattice. In a strictly molecular sense, diamond is similar to one big alkane.
 
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"Dissolve" in this context is so general a term it becomes meaningless.

In most cases "dissolve" means something disappears in contact with the solution (of acid), but it doesn't tell us what was the process/reaction behind. Metals typically get oxidized by H+, unless they are noble and require stronger oxidizers (like aqua regia, which technically is "just" a mixture of acids, yet it produces very strong oxidizing agent, completely unrelated to H+). Glass contains silicone dioxide, which reacts with HF producing gaseous SiF4 - that's a completely different situation and completely different reaction. Neither will work with diamond.

I don't remember hearing of acids capable of oxidizing diamond, there is no simple reaction/process which could make it happen. Could be there are some exotic cases though, chemistry is full of exceptions - but even if, the process behind will be completely unrelated to the ones mentioned.
 
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I suspect that by "dissolve" the OP actually means react.
For example a metal dissolving in acid is reacting, but I'll bet someone will come up with an exception to this. Also when stating hydrofluoric acid dissolves glass, it is reacting with it. But mainly ignore HF when thinking about acids in general.
If so, the OP should consider what diamonds are composed of, and then ask does that element react with acids. And then ask is there something special about the structure of diamond.
 
DrJohn said:
I suspect that by dissolve the OP actually means react.
For example a metal dissolving in acid is reacting, but I'll bet someone will come up with an exception to this. Also when stating hydrofluoric acid dissolves, glass, it is reacting with it. But mainly ignore HF when thinking about acids in general.
If so, the OP should consider what diamonds are composed of, and then ask does that element react with acids. And then ask is there something special about the structure of diamond.
It seems that the surface of carbons are reactive (not surprising), so perhaps strong reagents could eat away at the outer layer, and slowly compromise the structructure, but at room temperature? Unlikely.
 
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