The reactivity of sodium metal with water is utilized in which of the following processes?

Select the correct order :-

What is the product formed when sodium reacts with an excess of oxygen/air?

Among the following,which has the maximum hydration energy?

Given below are two statements:
Statement $I$: The chlorides of $Be$ and $Al$ have $Cl^{-}$-bridged structure. Both are soluble in organic solvents and act as Lewis acids.
Statement $II$: Hydroxides of $Be$ and $Al$ dissolve in excess alkali to give beryllate and aluminate ions.
In the light of the above statements,choose the correct answer from the options given below.

What is the product formed when sodium is heated in a current of dry ammonia?