polyatomic ion consists of more than one atom
sulphate is polyatomic ion
Answer:
I think the answer will be number A
On the left side. The alkali metals are group 1, the alkaline earth metals are group 2, and the transition metals are groups 3-12.
Answer: helium(He)
Explanation: Helium has only 2 electrons in the outermost energy level, but all of the other elements in its column have eight.
