topic 7181
Cleaning Pennies
2001
Hi, I'm doing a project for my third grade science fair. I have to find out what juices clean pennies the best. What juices should I choose and why? Thank you.
Marissa P.- Lancaster, New York,USA
2001
Choose the juices you don't like to drink, Marissa; use them this way and you'll run out of them and won't have to drink them.
When you say "clean pennies", you don't really mean "clean soil off of pennies". What you really mean is "dissolve the brown copper tarnish".
Sugar water will not dissolve anything, whereas sourness indicates a high acid content which is good for cleaning, and saltiness indicates chloride which is another good cleaner. So salty and sour drinks are probably the best cleaners.
But "why" is actually a very complex question in this case -- involving pH, chlorides, organic acids, chelators and complexers -- and your teachers probably don't even truly understand why one juice works better than others.
Conduct the experiment, accurately record the results without being swayed by expectations, and you will have achieved a lot!
Ted Mooney, P.E.
finishing.com - Pine Beach, New Jersey
Striving to live Aloha
2001
Marissa you should use Lemon juice it works great. I use it in my 7th grade sci. project. Oh and you should use things you don't like because then you can just throw them away after. Pretty smart huh?
Whitney P- FL, USA
Ed. note: Please read our F.A.Q. on the subject. Good luck. And maybe visit your library and ask your librarian for help!