Answer:
I believe Na
Explanation:
Copper, because it is the only metal out of all of them.
Therefore copper is the only element that can loose electrons to have a positive charge, it is the most likely to become a cation.
The answer would be Rocks, metals, hydrogen compounds, hydrogen and helium, all in gaseous form.
Answer:
isomers
Explanation:
Compounds that have the same molecular formula but different chemical structures are called isomers. Remember isomerism is a property between a pair (or more) of molecules, i.e. a molecule is an isomer of another molecule.