ammonium

[ uh-moh-nee-uhm ]

noun

, Chemistry.

1. the univalent ion, NH 4 + , or group, NH 4 , which plays the part of a metal in the salt formed when ammonia reacts with an acid.

ammonium

/ əˈməʊnɪəm; -njəm /

noun

1. modifier of, consisting of, or containing the monovalent group NH 4 – or the ion NH 4 ⁺

   ammonium compounds

ammonium

/ ə-mō′nē-əm /

1. A positively charged ion, NH 4 , derived from ammonia and found in a wide variety of organic and inorganic compounds. Compounds of ammonium chemically resemble the alkali metals.

Word History and Origins

Origin of ammonium¹

< New Latin; ammonia, -ium; coined by J. J. Berzelius in 1808

Example Sentences

Forest Service and other agencies each year drop tens of millions of gallons of fire retardant, mostly an ammonium phosphate-based slurry called Phos-Chek, around wildfires to coat vegetation and slow the spread of flames.

From Los Angeles Times

The MV Ruby's cargo of 20,000 tonnes of ammonium nitrate will be moved to another vessel at Great Yarmouth in Norfolk.

From BBC

The ship, owned by Maltese firm Ruby Enterprise, set off from the northern Russian port of Kandalaksha in July - with 20,000 tonnes of ammonium nitrate on board.

From BBC

Police posted photos of small cylinders of explosives with fuses and sacks of ammonium nitrate on the force’s social media accounts.

From Seattle Times

Takata used the volatile chemical ammonium nitrate to create a small explosion to quickly fill the air bags in a crash.

From Seattle Times