PH a pH of 7.3. This is clearly wrong as an acid solution should have a pH of less than 7. Treating the system as a mixture of hydrochloric acid and the amphoteric substance water, a pH of 6.89 results. A weak acid or the conjugate acid of a weak base can be treated using the same formalism. First, an acid dissociation constant is defined as follows. Electrical charges are omitted from subsequent equations for the sake of generality and its value is assumed to have been determined by experiment. This being so, there are three unknown concentrations, [HA], [H] and
Impedance–pH monitoring Impedance–pH monitoring Impedance–pH monitoring is a technique used in the diagnosis of gastroesophageal reflux disease (GERD), by monitoring both impedance and pH. Patients with ongoing symptoms while on proton-pump inhibitor (PPI) therapy are commonly diagnosed with impedance–pH monitoring while continuing their medications. The impedance–pH monitoring diagnostic test determines the frequency of reflux episodes and the time relationship of reflux episodes and symptoms. The impedance–pH monitoring test determines if the patient's symptoms are related to acid reflux, related to nonacid reflux, or not related to reflux of any type. A positive GERD diagnosis is made if acid or nonacid reflux precedes