Trioxonitrate (V) acid is not used for preparing hydrogen gas from metals because it
-
is strongly oxidizing
- is volatile
- renders the metal passive
- forms a layer of oxide on the metal
The correct answer is: A
Explanation
Nitric acid is not used in the preparation of hydrogen because it is a strong oxidizing agent, meaning it readily oxidizes the hydrogen gas produced during the reaction with a metal, converting it to water and thus preventing the collection of hydrogen gas; instead, acids like dilute hydrochloric acid or sulphuric acid are preferred for hydrogen production as they do not oxidize hydrogen.