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Author Topic: which one is the stronger element does not oxidize gold or platinum?  (Read 3002 times)

Offline taregg

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the same question....


 

Offline taregg

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please some body ask my question....
 

Offline Bored chemist

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I think there's a language problem here.
Are you asking if gold or platinum is harder to oxidise?
 

Offline taregg

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so which one harder for oxidise gold or  platinum ..... I mean
 

Offline Bored chemist

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Offline damocles

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Standard Electrode Potentials are about equilibrium situations; they are not concerned with rates of reaction. In a thermodynamic sense platinum is easier to oxidize than gold, but with most reagents this does not apply in a kinetic sense.

Problem is that if you can get gold to react, it will react fairly rapidly, whereas the oxidation reactions of platinum tend to be very slow. You can put a lump of gold in concentrated aqua regia (3:1 HCl:HNO3 at about 10 M total in water) at room temperature and watch it dissolve before your eyes. Platinum you have to reflux for a couple of days. (yes, I have actually tried and witnessed the results of both experiments).

Similarly gold tarnishes quite readily in an atmosphere of damp chlorine gas; platinum much more slowly. (This is only from reports; I have not witnessed it).
 

Offline lightarrow

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And which one oxides more easily with sulfur?  :)
 

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