A coin would dissolve in an acid, not melt. The time taken would depend on the size of the coin, its composition, and the acid used.
No, stomach acid cannot melt metal. Stomach acid, or hydrochloric acid, is strong enough to break down food for digestion, but it is not powerful enough to melt metal. Metal requires much higher temperatures to melt.
Only if the acid is above the melting point of copper. However, the copper might dissolve in acid if the acid is oxidizing. If it did, copper ions would be present in the solution formed, but there would not be an metallic copper in it.
Yes it can 'melt' metals.
yes
as it is acid ice cream will melt
Sulfuric acid and hydrochloric acid are known for their ability to melt metal.
A modern one dollar coin contains no real gold at all and the melt value of the coin is currently around six cents. As long as this coin is in circulation it will continue to be worth exactly one dollar.
acid
Yes, it is possible to melt a coin as most coins are made of metal. However, it is not recommended to do so as destroying currency is illegal in many countries. Additionally, the melting point of the metal will determine how easy or difficult it is to melt the coin.
You do not specify what country it is from or what the denomination is. Whatever the coin is, the melt value will be whatever the current price of gold is. Alternatively, it will probably be worth more as a collectible coin.
Sulfuric acid does not melt metal, it oxidizes it and dissolves it. Aluminum will react with sulfuric acid, but because of the protective coating of aluminum oxide the reaction is extremely slow.
Argon's a gas.