Final answer:
An acid releases H ions into a solution. Strong acids release all of their hydrogen ions into solution, while weak acids do not ionize completely.
Step-by-step explanation:
An acid releases H ions into a solution. When dissolved in water, acids dissociate into hydrogen ions (H+) and anions. Strong acids release all of their hydrogen ions into solution, while weak acids do not ionize completely. Hydrochloric acid (HCl) and vinegar (acetic acid) are examples of strong and weak acids, respectively.