Answer:
1
Explanation:
I believe it really only has 1 valence electrons
H30 are also known as hydroniums
An element is all the same thing. Pure, if you will.
The first one is definitely an element. The second would be a compound (it's atoms are different colors). I would say the last one is an element, since it has ll the same color of atoms.
I hope this helped you! If you have anymore questions, feel free to ask me.