What happens when you put a 2p in ketchup?

When you put a 2p coin in ketchup, the acidic nature of the ketchup can cause a chemical reaction with the copper in the coin. Over time, the coin may develop a tarnished appearance due to the formation of copper salts. However, the immediate effect is minimal, and the coin will not dissolve or be significantly damaged. It's a fun experiment, but it's best to avoid using valuable coins in such activities.