Indicate whether the following statement represents a chemical change, a physical change, or no change occurred: Hydrochloric acid was added to baking soda resulting in the evolution of carbon dioxide gas.

Indicate whether the following statement represents a chemical change, a physical change, or no change occurred: A red piece of copper wire is added to a beaker containing hydrochloric acid (a clear, colorless solution). After an hour a red wire is observed in a clear, colorless solution.