The key difference between ammonia and ammoniacal nitrogen is that the ammonia is an inorganic compound having the chemical formula NH3 whereas the ammoniacal nitrogen is a measure of the amount of ammonia in a sample.
Ammonia is a gaseous compound with a characteristic, pungent odor. Although it is useful on many occasions, it is a toxic compound as well. It is a common toxic pollutant in waste products such as sewage, manure, etc. We use ammoniacal nitrogen to measure the amount of this toxic compound.
CONTENTS
1. Overview and Key Difference
2. What is Ammonia
3. What is Ammoniacal Nitrogen
4. Side by Side Comparison – Ammonia vs Ammoniacal Nitrogen in Tabular Form
5. Summary
What is Ammonia?
Ammonia is an inorganic compound having the chemical formula NH3. Therefore, it is a gaseous compound with a characteristic, pungent odor. The IUPAC name of this compound is azane. The molar mass is 17 g/mol and the boiling point is −33.34 °C. One ammonia molecule has one nitrogen atom bonded to three other hydrogen atoms via covalent bonds. Moreover, this molecule has trigonal pyramidal shape, and it is a colorless gas that is lighter than normal air.
Figure 01: Chemical Structure of Ammonia
There are hydrogen bonds between ammonia molecules. Therefore, we can easily liquefy this gas. This compound is common in nitrogenous waste of aquatic organisms. Moreover, it contributes to the nutritional needs of terrestrial organisms; by providing food and fertilizer needs. However, in its concentrated form, ammonia is hazardous and caustic.
What is Ammoniacal Nitrogen?
Ammoniacal nitrogen is a measure of the amount of ammonia in a sample. Here, we determine the toxic effect of ammonia in landfill leachates, waste products such as manure, etc. Therefore, we measure the health of natural water bodies because ammonia can directly poison us at high concentrations. We denote ammoniacal nitrogen as NH3-N.
Figure 02: Nitrogen Cycle shows the Ammoniacal Nitrogen Forms in Environment
The unit of measurement is mg/L. In this measurement, we measure all the ammonia forms; ammonia (NH3), ammonium (NH4+), nitrogen gas (N2), nitrates (NO3–), nitrites (NO2–), organic nitrogen such as proteins, DNA, etc.
What is the Difference Between Ammonia and Ammoniacal Nitrogen?
Ammonia is an inorganic compound having the chemical formula NH3. It is useful at low concentration and toxic at high concentrations. Ammoniacal nitrogen is a measure of the amount of ammonia in a sample. It measures the amount of ammonia at its toxic levels. Moreover, it refers to all the ammonia forms such as ammonia (NH3), ammonium (NH4+), nitrogen gas (N2), nitrates (NO3–), nitrites (NO2–), organic nitrogen such as proteins, DNA, etc.
Summary – Ammonia vs Ammoniacal Nitrogen
Ammonia and ammoniacal nitrogen are two related terms. The difference between ammonia and ammoniacal nitrogen is that the ammonia is an inorganic compound having the chemical formula NH3 whereas the ammoniacal nitrogen is a measure of the amount of ammonia in a sample.
Reference:
1. “Ammonia.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine. Available here
2. “Ammoniacal Nitrogen.” Wikipedia, Wikimedia Foundation, 10 July 2018. Available here
Image Courtesy:
1.’Ammonia-2D’By Radio89 – Own work, (CC BY-SA 3.0) via Commons Wikimedia
2.’Nitrogen Cycle’By Burkhard (CC BY-SA 3.0) via Commons Wikimedia