Are Ammonia (NH3) and Ammonium (NH4+) different substances?

Document ID

Document ID TE1930

Published Date

Published Date 21/01/2019
Question
Are Ammonia (NH3) and Ammonium (NH4+) different substances?
Summary
Amtax sc Measurements
Answer
Ammonia and Ammonium always come in equilibrium when dissolved in fluids (water). Dependent on pressure, temperature and most importantly the pH value, the proportion of the NH3 and NH4+ vary as the molecules dissociate. In alkaline fluids the Ammonia is the dominant molecule. Keep in mind that other ammonia instrumentation (lab or process) may report differently. When comparing the Amtax sc analyser to a laboratory measurement which could be expressed in different terms like NH3 or NH3-N, the customer may see some minor differences in measured values.