Final answer:
A strong acid or base fully dissociates into ions in water, making them strong electrolytes, while a weak acid or base partially dissociates, resulting in a solution with both ions and undissociated molecules.
Step-by-step explanation:
In the context of dissociation, a strong acid or strong base fully dissociates into ions when dissolved in water. This means that virtually every molecule of a strong acid, like hydrochloric acid (HCl), dissociates to yield a high concentration of hydrogen ions (H+) and the corresponding anion, chloride (Cl-).
On the other hand, a weak acid or weak base only partially dissociates in water, resulting in a solution that contains both ions and undissociated molecules. The extent of dissociation of a weak acid or weak base is often less than 5%, meaning that the majority of the substance remains in its molecular form in solution.
Furthermore, strong acids and bases are considered strong electrolytes as they conduct electricity well due to their complete dissociation into ions, whereas weak acids and bases are weak electrolytes. The strength of an acid or base is not to be confused with its solubility; a strong base can be less soluble than a weak base, and vice versa, but solubility does not affect whether a substance is considered a strong or weak electrolyte.