Copper + sulfuric acid + H2O = stink?

  • Thread starter Thread starter Mustard Tiger
  • Start date Start date
  • Tags Tags
    Acid Copper
Click For Summary

Discussion Overview

The discussion centers around the chemical reactions that occur when copper is introduced to concentrated sulfuric acid and subsequently rinsed with water, particularly focusing on the production of a foul odor and the possible gases involved, such as hydrogen sulfide or sulfur dioxide.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant observes that rinsing copper with water after exposure to sulfuric acid produces a bubbling reaction and a rotten egg smell, questioning the identity of the gas released.
  • Another participant confirms that the smell is likely due to hydrogen sulfide and suggests that the copper may have had traces of sulfide prior to the reaction.
  • A different participant proposes that elevated temperatures are necessary for sulfuric acid to be reduced to sulfur oxides by copper, suggesting that sudden dilution of the acid could create such conditions.
  • There is a mention that while copper can reduce sulfuric acid, it may not do so significantly without the right conditions.

Areas of Agreement / Disagreement

Participants express differing views on the chemical processes involved, particularly regarding the necessity of elevated temperatures and the potential for copper to reduce sulfuric acid. There is no consensus on the exact reactions that occurred.

Contextual Notes

Participants note the possibility of prior sulfide traces on the copper and the conditions under which sulfuric acid might be reduced, but these points remain speculative and unresolved.

Mustard Tiger
Messages
1
Reaction score
0
I put some copper bits into concentrated sulfuric acid. Nothing much happened other than it got shiny and clean looking. So I poured off the acid and then put water on the copper to rinse off the remaining acid, and the copper started bubbling and made a nasty rotten egg smell. Is that hydrogen sulfide or sulfur dioxide or what? What chemical reactions happened here?
 
Chemistry news on Phys.org
Do a search on rotten egg smell.
 
Mustard Tiger said:
Is that hydrogen sulfide

Yes.

What chemical reactions happened here?

Most likely the copper surface was covered with traces of sulfide earlier. While technically it is possible for the sulfuric to be reduced by copper, I don't think it will go that far.
 
  • Like
Likes   Reactions: hilbert2
I think elevated temperatures are needed for sulfuric acid to be reduced to sulfur oxides by copper. That kind of heating can be caused by sudden dilution of the acid, in principle.
 

Similar threads

Replies
16
Views
4K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
1
Views
2K
Replies
1
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
Replies
1
Views
5K
  • · Replies 18 ·
Replies
18
Views
6K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 3 ·
Replies
3
Views
5K