hydrogen ion

noun

1

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

2

: hydronium

Example Sentences

Recent Examples on the Web

The first product of that reaction is a compound called carbonic acid, which soon gives up its hydrogen ion. —WIRED, 2 Nov. 2022

At this point, lactate can’t grab its hydrogen ion to reduce the concentration of hydrogen in the muscle cell. —Jeff Gaudette, Outside Online, 3 Oct. 2018

For each lactate molecule produced by the body, one hydrogen ion is also formed. —Jeff Gaudette, Outside Online, 3 Oct. 2018

Meanwhile, on the tube’s outer surface, the second catalyst—which contains vanadium, nitrogen, and iron—causes the hydrogen ions, the electrons, and nitrogen molecules piped in separately to form ammonia, all at atmospheric pressure. —Robert F. Service, Science | AAAS, 6 Nov. 2019

As the carbon mixes into the ocean, chemical reactions in the water column produce more hydrogen ions and fewer carbonate ions, lowering pH levels and increasing acidity. —oregonlive, 24 Jan. 2020

When that carbon is absorbed, a series of chemical reactions takes place that produces more hydrogen ions and leads to more acidic waters. —Sarah Gibbens, National Geographic, 4 Mar. 2019

But hydrogen ions, single protons, have positive electric charges and naturally repel each other. —Tim Folger, Discover Magazine, 24 Oct. 2018

The more hydrogen ions present, the more acidic the solution will be, and the lower the pH. —SELF, 6 Sep. 2018

See More

Word History

First Known Use

1896, in the meaning defined at sense 1

Kids Definition

hydrogen ion

noun

: the positive ion of acids that consists of a hydrogen atom whose electron has been transferred to the negative ion of the acid

Medical Definition

hydrogen ion

noun

1

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

2

: hydronium