Question

what does fizzing from dropping hydrochloric acid onto a piece of limestone indicate about the chemical reaction? the reaction produces a gas. the reaction absorbs light. the reaction changes in color.

Explanation:

Fizzing is a sign of gas - formation in a chemical reaction. When hydrochloric acid reacts with limestone (calcium carbonate), carbon dioxide gas is produced, causing the fizzing. Absorbing light and color - change are not indicated by fizzing.

Answer:

The reaction produces a gas.