Question

Salt water is a good conductor. When salt is dissolved in water, which of following explains why it becomes a good conductor?



(2 points)

The salt dissolving require physical mixing to move the charges

The salt dissolving frees the electrons in the solution, allowing them to move freely

The salt dissolving generates a large amount of heat which is used to carry current

The salt dissolving breaks down the insulating molecules of the water

Answer 1

Choose: "The salt dissolving breaks down the insulating molecules of the water" (option 4).

Reason: When salt (e.g., NaCl) dissolves it dissociates into ions (Na+ and Cl−). These mobile charged ions, not free electrons, move under an electric field and carry electric current. Water's polarity helps solvate (stabilize) those ions so they can move.