Statement I : ‘Al’ utensils should not be kept in water over night.
Statement II : ‘Al’ may get oxidized to Al+3 ions which are more toxic.
In the oxidation state of Al is +3 .
Ionisation energy is absorbed energy for the removal of three electrons.
Where as hydration energy is released energy during hydration of one mole of Al+3 ions.
In the above reaction both the processess are involved but hydration energy is greater than that of ionisation energy.
Hence removal of three electrons easily takes place and gives Al+3 ion in solution.
Therefore "Al" gets oxidised to Al+3 ions which are more toxic hence we cannot store water in Al vessels.