Give reason why nitric acid cannot …

Nitric acid is strong oxidising agent . It oxidises the hydrogen formed by water.

... Actually the main thing is Nitric acid is strong oxidising agent . It oxidises the hydrogen formed by water.

-As we know that nitric acid has another name that is aqua fortis which is a highly corrosive acid. The molecular formula of nitric acid consists of one hydrogen, one nitrogen and 3 oxygen molecules. -Also, nitric acid is also a strong oxidising agent because it can oxidise other molecules by giving an oxygen molecule and reduces itself. -Now, we know that hydrogen gas consists of two atoms of hydrogen which combine when metal and water react together. -Metals such as sodium, magnesium, manganese, etc can be used to react with a cheap compound that is water to liberate the hydrogen gas. -The balanced chemical reaction is: 2Na + 2H2O → 2NaOH + 2H2 -But if we use the dilute nitric acid then it will act as an oxidising agent and react with hydrogen gas to produce water molecules. -As we can see in the chemical reaction: 2HNO3 + H2 → 2H2O + 2NO2 Therefore, due to the oxidation of hydrogen gas by dilute nitric acid, nitric acid is not used for the preparation of hydrogen gas.