Final answer:
In chemistry, a strong acid or base completely dissociates in water, while a weak acid or base only partially dissociates. The strength of an acid or base is determined by the extent of dissociation. For example, hydrochloric acid is a strong acid, while acetic acid is a weak acid.
Step-by-step explanation:
In chemistry, the terms "strong acid" and "strong base" refer to substances that completely dissociate in water, while "weak acid" and "weak base" refer to substances that only partially dissociate. The strength of an acid or base is determined by the extent of dissociation.
For example, hydrochloric acid (HCl) is a strong acid because it dissociates completely in water to produce H+ ions and chloride ions (Cl-). On the other hand, acetic acid (CH3COOH) is a weak acid because it only partially dissociates to produce a small amount of H+ ions and acetate ions (CH3COO-).
Similarly, sodium hydroxide (NaOH) is a strong base because it dissociates completely in water to produce Na+ ions and OH- ions. In contrast, ammonia (NH3) is a weak base because it only partially reacts with water to produce a small amount of NH4+ ions and OH- ions.