Question

Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH₃COOH) is added to test tube B. In which test tube will the fizzing occur more vigorously, and why?

Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH₃COOH) is added to test tube B. The amount and concentration taken for both acids are the same. In which test tube will the fizzing occur more vigorously, and why?

Answer 1

The fizzing will occur strongly in test tube A, in which hydrochloric acid (HCl) is added. This is because HCl is a stronger acid than CH₃COOH and therefore produces hydrogen gas at a faster speed, due to which fizzing occurs.

Answer 2

HCl is a strong acid, whereas acetic acid is a weaker acid. Fizzing occurs because the hydrogen gas evolves by reacting with the acid on the magnesium ribbon. Since HCl is a very strong acid, there is a lot of hydrogen gas liberated from test tube A. Therefore, more fizzing takes place in test tube A.