JAMB - Chemistry (2018 - No. 63)
Aluminium does not react with either dilute or concentrated trioxonitrate (V) acid because
it is insoluble in either dilute or concentrated trioxonitrate (V) acid
it is lower than hydrogen in the electrochemical series
the reaction with trioxonitrate (V) acid has a light activation energy
an insoluble oxide is formed on its surface which renders it passive
Açıklama
Aluminium doesn’t react with either dilute or concentrated trioxonitrate (V) acid because an insoluble oxide is formed on its surface which renders it passive. It will depend on the concentration of the nitric acid used…. Although aluminium reacts with dilute nitric acid to produce aluminium nitrate and hydrogen gas, concentrated (>60%) nitric acid is such a powerful oxidising agent that it instantly causes a thin layer of aluminium oxide to coat the surface of the aluminium