Sodium chloride does not conduct electricity when solid but conducts when molten. What is the reason?
Answer and explanation
Correct answer: D. In the molten state the ions are free to move
- Step 1: Conduction needs charged particles that can move.
- Step 2: In the solid lattice the ions are fixed; once molten they are free to move and carry charge.
Answer
In the molten state the ions are free to move.
Why not the others: Molten sodium chloride contains free electrons: free electrons exist in metals. Solid sodium chloride has no charged particles: it contains ions in a fixed lattice. Melting turns the ions into atoms: ions stay as ions when melted.
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