Question

Josh decided to mix some vinegar with baking soda. He knew that a reaction occurred because he made careful observations. He noted that the mixture started to foam up and bubble and was white in color. How did Josh know that a chemical reaction occurred? He was sure a reaction occurred because of
Responses

A the formation of a gas.the formation of a gas.

B the color of the mixture.the color of the mixture.

C the smell of the vinegar.the smell of the vinegar.

D the volume of the mixture.

Answer 1

A — the formation of a gas.

The bubbling and foaming are evidence that carbon dioxide gas was produced when acetic acid (vinegar) reacted with sodium bicarbonate (baking soda), which is a clear sign of a chemical reaction.