[Chemistry] Salt in an acetic acid solution with copper

[bnosam]

Homework Statement

Basically I'm doing a lab report where we place copper pennies in a solution of salt and vinegar. This should strip the copper oxide off the outside of the pennies, leaving the copper underneath shiny and looking "new".

The problem is why we add the salt.

Homework Equations

The main reaction is with the copper oxide and the vinegar.

2 C₂H₄O₂ + Cu ===> Cu(C₂H₃O₂)₂ + H₂

The Attempt at a Solution

I've looked online and I see some people's opinions are that the salt was added so the chlorine in it would combine with some hydrogen to form hydrochloric acid, however, wouldn't the bonds between NaCl be too strong for this to happen in an acid like vinegar?

My guess is that salt somehow speeds this up because it is corrosive to metals?

 

[Borek]

http://pubs.acs.org/doi/abs/10.1021/ed078p513

 

[bnosam]

http://pubs.acs.org/doi/abs/10.1021/ed078p513

Thank you for the link, but is there any free literature on this? It appears that website requires a subscription or that I buy access for the article.

 

[Borek]

Paper is from the Journal of Chemical Education, check if your library doesn't have it. I am not aware of other papers (doesn't mean they don't exist).

 

[bnosam]

Paper is from the Journal of Chemical Education, check if your library doesn't have it. I am not aware of other papers (doesn't mean they don't exist).

I checked and they don't have any papers by the Journal of Chemistry on file or available in the online library. The best they could do is get me permission to view the paper at a university that has it 2 hours away.

Thanks though!