ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm 
: an ion NH4+ derived from ammonia by combination with a hydrogen ion and known in compounds (such as salts) that resemble in properties the compounds of the alkali metals
Examples of ammonium in a Sentence
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The chemical ammonium perchlorate is one of many controlled by the Missile Technology Control Regime, an agreement between countries to limit the proliferation of missiles and missile technology, according to the U.S. Department of State.
—
John Yoo and John Shu, Newsweek, 24 Jan. 2025
The misconception may spring in part from the fact that methyl ammonium lead triiodide, which is still widely used by academic researchers, is one of the unstable compounds.
—IEEE Spectrum, 4 Jan. 2019
Instead, modelling predicts the clouds are most likely composed of ammonium hydrosulfide and possibly smog produced by photochemical reactions in the atmosphere, as the coloration of the clouds is not consistent with pure ices.
—Victoria Corless, Space.com, 9 Jan. 2025
This protein powder is produced by a microorganism found in the Baltic Sea, which essentially feeds on hydrogen, carbon dioxide, ammonium, and oxygen in bioreactors.
—Christine Ro, Forbes, 20 Oct. 2024
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John Yoo and John Shu, Newsweek, 24 Jan. 2025
The misconception may spring in part from the fact that methyl ammonium lead triiodide, which is still widely used by academic researchers, is one of the unstable compounds.
—IEEE Spectrum, 4 Jan. 2019
Instead, modelling predicts the clouds are most likely composed of ammonium hydrosulfide and possibly smog produced by photochemical reactions in the atmosphere, as the coloration of the clouds is not consistent with pure ices.
—Victoria Corless, Space.com, 9 Jan. 2025
This protein powder is produced by a microorganism found in the Baltic Sea, which essentially feeds on hydrogen, carbon dioxide, ammonium, and oxygen in bioreactors.
—Christine Ro, Forbes, 20 Oct. 2024
See all Example Sentences for ammonium
Dictionary Entries Near ammonium
Cite this Entry
“Ammonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ammonium. Accessed 3 Feb. 2025.
Copy CitationKids Definition
ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm
: an ion that comes from the combination of ammonia with a hydrogen ion
Medical Definition
ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm
: an ion NH4+ derived from ammonia by combination with a hydrogen ion and known in organic compounds (as quaternary ammonium compounds) and in compounds (as salts) that resemble in properties the compounds of the alkali metals
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