Strong acids are characterized by which in aqueous solution?

• A. They partially dissociate
• B. They do not ionize
• C. They fully dissociate
• D. They only weakly dissociate

Answer: (C)

Strong acids in water act as complete proton donors: every molecule donates its proton to water, producing hydronium ions and the conjugate base. The equilibrium lies far to the right, so essentially all of the acid exists as ions, and [H3O+] is established at a high level. This complete ionization is what makes strong acids good conductors in solution and is the defining feature described by “fully dissociate.” In contrast, acids that only partly ionize are weak acids, so describing a strong acid as partially or not ionizing would mischaracterize its behavior. For example, HCl in water converts to H3O+ and Cl− almost completely, illustrating this full dissociation and resulting high acidity.