I'm not a chemist and I can't really remember how this works, but the sodium in the trisodium citrate (Na3C6H5O7) is more reactive than the copper in the copper alloy in the coin. So the copper shouldn't displace the sodium in the acid, therefore no reaction. Right?
I'm not a chemist and I can't really remember how this works, but the sodium in the trisodium citrate (Na3C6H5O7) is more reactive than the copper in the copper alloy in the coin. So the copper shouldn't displace the sodium in the acid, therefore no reaction. Right?