Predict whether ionic and covalent compounds would conduct electricity in the molten state (the melted state of a substance).
Ionic compounds do not conduct electricity in the solid state because their ions are held in fixed positions by strong forces. In the molten state, these forces are overcome, allowing the ions to become free to move. Therefore, ionic compounds will conduct electricity in the molten state.
On the other hand, covalent compounds do not provide ions; they consist of neutral molecules. Because there are no free ions available to carry an electric charge, covalent compounds will not conduct electricity even in the molten state.
Explanation
The textbook explains that ionic compounds do not conduct electricity in the solid state because their ions are held in fixed positions. To conduct electricity, ions must be free to move. In the molten state, the strong inter-ionic forces are broken, freeing the ions to move and conduct electricity. Conversely, covalent compounds do not provide ions in solution or otherwise, meaning they lack the charged particles necessary to conduct electricity in any state, including molten.
Solution Steps
Step 1: Analyze ionic compounds—since ions must be free to move to conduct electricity and melting overcomes the strong forces holding them in fixed positions, ionic compounds will conduct electricity in the molten state.
Step 2: Analyze covalent compounds—since they do not provide ions (consisting of neutral molecules), they will not conduct electricity even in the molten state.