dilute H2SO4+Cu

2012-03-18 6:57 am
Is there any reaction between dilute sulphuric acid and copper metal?

some says no but why? Dilute H2SO4 should contains SO42- ions which can be easily (reduced?) to SO2
How about dilute nitric acid+copper metal?Also why dilute nitric acid is reduced to nitrogen monoxide while concentrated one is reduced to nitrogen dioxide?

回答 (3)

2012-03-18 11:01 pm
✔ 最佳答案
when it is an OA , It is in liquid state.
it means that it is a molecule. So, only H2SO4 can act as a OA but not SO4 2-.
Both of them are redox reaction, not neuturalization.

NO3-(aq) + 4 H+(aq) + 3 e- -----> NO(g) + 2 H2O E=+0.96
NO3-(aq) + 2 H+(aq) + e- -----> NO2(g) + H2O (for concentrated) E=>+0.96
Cu2+(aq) + 2 e- -----> Cu(s) E=+0.34
2NO + O2 ----->NO2 ( which is redox too, you may write the half eqt for both reactant)
dilute
Ecell = 0.96-0.34=0.62V
conc.
Ecell >0.62V
so NO3- directly convert to NO2 instead of oxidation with O2.
However, it is my guess. If i am wrong, hope anyone can correct it



2012-03-18 15:02:18 補充:
it should be no reaction because it is a typical acid in dilute

2012-03-18 15:58:19 補充:
since HNO3(aq) is an oxidizing agent already
HNO3(l) is also a oxidizing agent
The difference is ,high concentration, most of it exists in molecule.
If you want the reason why HNO3 has oxidizing property, I hope other advanced users can anwser you
2012-03-27 6:00 am
conc. H2SO4 react with Cu by redox reaction
conc HNO3 react with metal , evolving NO2
dilute HNO3 react with metal producing NO
2012-03-26 12:40 am
Is there any reaction between dilute sulphuric acid and copper metal?
No.


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