hydrogen ion

American  

noun

1. ionized hydrogen of the form H + , found in aqueous solutions of all acids.

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hydrogen ion British  

noun

1. an ionized hydrogen atom, occurring in plasmas and in aqueous solutions of acids, in which it is solvated by one or more water molecules; proton. Formula: H ⁺

2. an ionized hydrogen molecule; hydrogen molecular ion. Formula: H 2 ⁺

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Etymology

Origin of hydrogen ion

First recorded in 1895–1900

Example Sentences

The changes in molecular vibrations of the pMBA molecules, which vary with hydrogen ion adsorption, serve the function of memory and nonlinear waveform transformation for calculation.

From Science Daily • Apr. 26, 2024

In the reaction, a molecule of hydrogen gas collides with one deuterium ion to produce a hydrogen ion and a heavy, deuterium-containing hydrogen molecule.

From Scientific American • Apr. 4, 2023

A hydrogen ion gradient is established by pumping two hydrogen ions across the membrane from the matrix in the intermembrane space.

From Textbooks • Jun. 9, 2022

Aqueous solutions are basic because the carbonate ion accepts hydrogen ion from water in this reversible reaction:

From Textbooks • Feb. 14, 2019

Such acids as hydrochloric and nitric acids, which have only one replaceable hydrogen atom in the molecule, or in other words yield one hydrogen ion in solution, are called monobasic acids.

From An Elementary Study of Chemistry by McPherson, William