Need help with science experiment calculations

AI Thread Summary
The discussion revolves around calculating the composition of copper coins after an experiment that turns them into 'silver' and 'gold.' Participants are seeking assistance with determining the percentages of brass, copper, and steel in the coins, as well as the amount of zinc dissolved and formed during the process. A key point raised is the varying material composition of U.S. pennies based on their minting year, which affects calculations. The conversation emphasizes the importance of knowing the specific type of coins used in the experiment for accurate results. Overall, the thread aims to clarify the necessary calculations for a successful analysis of the experiment's outcomes.
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me and my partner did an experiment of turning copper coins into 'silver' and 'gold'
we used this site or the info:
http://www.nuffieldfoundation.org/practical-chemistry/turning-copper-coins-silver-and-gold

But we're having trouble with knowing how to make the calculations of :

How much % brass, copper and steel is now in the coin after the experiment?
How much zinc dissolved and formed sodium zincate?
How much zinc was formed on the copper coin?

Can anyone please give us some suggestions on what we could do.
 
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ok let's first start out with the first question in mind,

what was your first calculation of the copper coins? first of all, did u use actual copper coins, or straight up pennies? cause if you used pennies, its going to be a bit difficult. if you gathered a bunch of pennies and did the experiment, then u got to notice the factor that each era of penny in the USA has different material composition. depending on its years.

here's a chart to explain: Years Material
1793–1857 100% copper
1857–1864 88% copper, 12% nickel (also known as NS-12)
1864–1942 1946–1962 bronze (95% copper, 5% tin and zinc)
1943 zinc-coated steel (also known as 1943 steel cent)
1944–1946 brass (95% copper, 5% zinc)
1962–1982 brass (95% copper, 5% zinc)
1982–present 97.5% zinc, 2.5% copper (core: 99.2% zinc, 0.8% copper; plating: pure copper)start off with the first calculation question, reply back and I'll see how to set this up.
 
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