* Chemical Reaction: Limestone (calcium carbonate, CaCO₃) reacts with acids (like hydrochloric acid, HCl) to produce carbon dioxide gas (CO₂), water (H₂O), and a salt (calcium chloride, CaCl₂). This is a chemical reaction because new substances are formed.
* Fizzing is Gas Release: The fizzing you see is the release of carbon dioxide gas, which is a product of the chemical reaction.
* Irreversible Change: The reaction cannot be easily reversed to get back the original limestone and acid.
In summary: The reaction between limestone and acid is a chemical change because it involves the formation of new substances and the release of gas.
