This was a chemical reaction. We can determine this because a new substance was formed as indicated by the appearance of bubbles.
This was a chemical reaction. We can determine this because new substances were formed with different properties than the original substances. In this case, magnesium reacted with hydrochloric acid to produce magnesium chloride and hydrogen gas. The production of small bubbles on the metal strip indicates the release of hydrogen gas, which is evidence of a chemical reaction taking place.
