hydrogen ion

noun

|Updated on: 8 Aug 2018

Definition of hydrogen ion

1 : the cation H⁺ of acids consisting of a hydrogen atom whose electron has been transferred to the anion of the acid

2 : hydronium

Recent Examples of hydrogen ion from the Web

At the cathode, catalysts split N2 molecules and prompt the hydrogen ions and electrons to react with nitrogen and make ammonia.

— robert f. service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018
The anode, covered with a catalyst, splits water molecules into O2, hydrogen ions, and electrons.

— robert f. service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018
Further testing showed that the feet contained a molecular pump that moves around hydrogen ions, or protons, to make acid.

— veronique greenwood, New York Times, "This Burrowing Clam Is Not Boring. It Uses Acid to Make Its Home.," 14 June 2018
The radio waves are calibrated to target just the less abundant material, in this case hydrogen ions.

— jay bennett, Popular Mechanics, "MIT Achieves Breakthrough in Nuclear Fusion," 28 Aug. 2017
The excited hydrogen ions then slam into the more abundant deuterium ions, and resulting particles fly into the reactor's outer shell, generating heat and electricity.

— jay bennett, Popular Mechanics, "MIT Achieves Breakthrough in Nuclear Fusion," 28 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hydrogen ion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.