Final answer:
MgBr₂, Na₂CO₃, and KOH are strong electrolytes because they fully dissociate into ions in water, while C₁₂H₂₂O₁₁ is a nonelectrolyte as it dissolves without dissociation into neutral molecules.
Step-by-step explanation:
To classify each compound as a strong electrolyte or a nonelectrolyte, we need to understand how they dissociate in water:
- MgBr₂ is an ionic compound that dissociates completely in water into its ions, Mg2+ and Br-, and so it is classified as a strong electrolyte.
- C₁₂H₂₂O₁₁, which is table sugar, does not dissociate into ions in water. Instead, it dissolves as individual sugar molecules, making it a nonelectrolyte.
- Na₂CO₃ is an ionic compound that fully dissociates into Na+ and CO₃2- ions, thus it is a strong electrolyte.
- KOH is also an ionic compound and dissociates into K+ and OH- ions in solution, so it too is a strong electrolyte.