I Figured out why the Coins look Different
Remember the coin experiment that I performed lately?
When I washed the coins, they looked different.
I finally figured out the answer.
Copper metal is oxidized by the Ag1+ to Cu2+ and the Ag1+ ions are reduced by the copper metal to silver metal.
But do you remember what the coins are made of?
Penny: The alloy remained 95 percent copper and 5 percent zinc until 1982, when the composition was changed to 97.5 percent zinc and 2.5 percent copper (copper-plated zinc) until now. Cents of both compositions appeared in that year.
50 Satang (Thai baht): The core is 99% iron and cladding is 99% Copper.
10 Yen (Japanese Yen): 95% copper, 3–4% zinc, and 1–2% tin.
The Penny turned yellow-orange because the zinc was mixed with copper.
The Thai coin turned darker because of the iron.
The Japanese coin turned yellow because of the zinc and tin. Tin is light yellow and zinc is gray.
I hope you enjoyed that experiment, if you did, comment down below ↓