Which of the following best describes a net ionic equation?

• A. It shows the physical states of all compounds but does not indicate ionic dissociation.
• B. It shows only the species that actually participate in the chemical reaction, omitting spectator ions.
• C. It represents only the molecular form of the reactants and products.
• D. It includes all ions present in the solution, including spectator ions.

Answer: (B)

Verified step by step guidance

1. Understand that a net ionic equation focuses on the species that undergo a chemical change during a reaction, excluding ions that do not participate (spectator ions).
2. Recall that in aqueous solutions, many compounds dissociate into ions, but not all ions are involved in the actual chemical transformation.
3. Recognize that a net ionic equation is derived by first writing the balanced molecular equation, then the complete ionic equation showing all ions separately, and finally removing the spectator ions to leave only the reacting species.
4. Note that the net ionic equation includes the physical states of the species involved to provide context about their form (solid, liquid, gas, aqueous).
5. Conclude that the best description of a net ionic equation is that it shows only the species that actually participate in the chemical reaction, omitting spectator ions.