When polyatomic ions dissolve in water, do they dissociate into their constituent atoms?

• A. Polyatomic ions partially dissociate, releasing some but not all of their atoms.
• B. No, polyatomic ions remain intact and do not dissociate into individual atoms.
• C. Yes, polyatomic ions completely dissociate into their individual atoms.
• D. Polyatomic ions react with water to form new compounds.

Answer: (B)

Verified step by step guidance

1. Understand what a polyatomic ion is: it is a charged species composed of two or more atoms covalently bonded together that act as a single unit with a net charge.
2. Recall that when ionic compounds dissolve in water, they dissociate into their constituent ions, not into individual atoms.
3. Recognize that polyatomic ions remain intact as a whole unit when dissolved; they do not break apart into individual atoms because the covalent bonds within the ion are strong and not broken by the dissolution process.
4. Therefore, in aqueous solution, polyatomic ions exist as complete ions rather than separate atoms.
5. Conclude that the correct understanding is that polyatomic ions do not dissociate into individual atoms but stay intact as ions in solution.