Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: pcm81 on January 12, 2018, 05:50:42 PM
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Hi. It's been about 15 years since my last college chemistry class and i can't remember the name of the property i am looking for to find it online. As I recall there is more to acids reacting with metals than acid disassociation constant characterizing acid strength... After all a strong sulphuric acid cant dissolve gold, but HCL + Nitric mixture can. What is the name of the propetry i am looking for that will tell me which acids can and cannot dissolve which metals. I think it has something to do with nobilty of metals too...
Thanks ahead.
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I don't think there is a single term covering what you are looking for. Some metals need strong oxidizers to dissolve. H+ is an oxidizer, but not strong enough. In general it is about redox potentials, but as a rule of thumb you can use reactivity series.
Hopefully some of these keywords will ring a bell for you.
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I don't think there is a single term covering what you are looking for. Some metals need strong oxidizers to dissolve. H+ is an oxidizer, but not strong enough. In general it is about redox potentials, but as a rule of thumb you can use reactivity series.
Hopefully some of these keywords will ring a bell for you.
If my memory serves me right it has something to do with oxidation reduction potential like in this chart:
http://eesemi.com/ox_potential.htm
Which is why HF pretty much dissolves everything since F has such much high potential.
Just was not sure if there is a table for acids vs metals allowing me not to think...
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If my memory serves me right it has something to do with oxidation reduction potential like in this chart:
Yes.
Which is why HF pretty much dissolves everything since F has such much high potential.
No. It is elemental fluorine (F2) that is a strong oxidizer, in HF fluorine is in a form of fluoride anion (F-), which is already reduced and not that reactive. Yes, it still has some interesting properties.
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The corrosion resistance of metals does not depend simply on a redox potential. It depends much on the quality of the surface oxide.
For instance Ta resists corrosion very well but isn't a noble metal.
Or Cr makes steel stainless despite its redox potentials are similar to Fe.