Is baking soda fizzing when mixed with vinegar a physical or chemical change?

The reaction between baking soda and vinegar is a chemical change. This is because the baking soda and vinegar undergo a reaction to form new products, carbon dioxide gas and water. The carbon dioxide gas causes the fizzing reaction, which is a sign that a chemical change has occurred.

To summarize, the fizzing reaction between baking soda and vinegar is a chemical change because new substances (carbon dioxide gas and water) are formed as a result of the reaction.