An acid is considered strong when it very easily releases H+ ions in an aqueous solution. An acid is considered weak, on the other hand, when it only partially releases H+ ions in an aqueous solution. An example of a strong acid is gastric acid (hydrochloric acid). An example of a weak acid is acetic acid. The strength of a base depends on how easily H+ ions are bound by this base. An example of a strong base is potassium hydroxide. An example of a weak base is ammonia.