Answer:
I think it is liquid's only.
Explanation:
There are many ways to predict the properties of an element here's one example.As you move from left to right the electron affinity and ionization energy both increase .Since elements of the same family have similar characteristic,you can often predict the properties of another element in its family
<h3>Answer:</h3>
Oxidation number refers to a number given to an atom which shows the number of number of electrons lost (or gained, if the number is negative), by an atom of that element in the compound.
Hence oxidation number of following atoms in given reaction are:
In NaOH:
Na = +1
O = -2
H = +1
In H2:
H = 0
Change in concentration/change in time.(C).