The answer is A, good luck
Answer: The correct option is 2.
Explanation: Polyatomic ions are defined as the ions in which two or more elements are covalently bonded to act as a single unit. They always carry some charge.
Examples of polyatomic ions are: 
known as hydroxide ion, 
known as sulfate ion
We are given a compound 
having 2 ions which are 
and 
. these ions are named as sodium ions and hydrogen carbonate ions.
Therefore, the correct option is 2.
Answer:
It's a type of chemical bond that emerges because of electrostatic force between electrons and positive metal charges.
Explanation:
I don't know if this is what you are looking for but i don't mind if you copy it.
Freezing something makes it solid and melting something makes it a liquid
