For a substance to be classified as an electrolyte, what must it do?

For a substance to be classified as an electrolyte, it must conduct electricity when dissolved in water or in a molten state. Electrolytes are typically ionic compounds that dissociate into ions in solution, allowing an electrical current to pass through. This property is essential because it enables various physiological processes in the human body, such as nerve signaling and muscle contraction, which rely on the movement of ions.

The other options do not accurately describe the requirements for a substance to be classified as an electrolyte. Absorbing water does not ensure that a substance will conduct electricity; rather, it is the dissociation into ions that is crucial. Additionally, while strong acids can be electrolytes, not all electrolytes must form strong acids, and the classification isn't limited to acidic substances. Lastly, many electrolytes do not exist solely in solid state; they can exist in liquid forms (as solutions) and still retain their ability to conduct electricity. Thus, the key characteristic that defines an electrolyte is its ability to conduct electricity through ionization.