hydrogen ion

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Related to Eigen cation: H3O+ ion, H+ Ion, Hydroxonium, Hydrogen ions

ion

 [i´on]
an atom or group of atoms having a positive (cation) or negative (anion) electric charge by virtue of having gained or lost an electron; substances forming ions are called electrolytes. adj., adj ion´ic.
dipolar ion an ion that has both positive and negative regions of charge.
hydrogen ion the positively charged hydrogen atom (H+), which is the positive ion of all acids. See also hydrogen ion concentration.
hydroxyl ion the negatively charged group, OH, present to excess in alkaline solutions.

hy·dro·gen ion (H+),

a hydrogen atom minus its electron and therefore carrying a unit positive charge (that is, a proton); in water, it combines with a water molecule to form hydronium ion, H5O2+, H7O3+, etc.

hydrogen ion [H+]

a positively charged hydrogen atom or proton.

hy·dro·gen ion

(H+ hī'drō-jen ī'on)
A hydrogen atom minus its electron and therefore carrying a unit positive charge (i.e., a proton); in water, it combines with a water molecule to form the hydronium ion, H3O+.

hydrogen ion

A free proton, which is the positively charged nucleus of a hydrogen atom.

ion

an atom or group of atoms having a positive (cation) or negative (anion) electric charge by virtue of having gained or lost one or more electrons. Substances forming ions are electrolytes.

ion channel
see channel.
dipolar ion
zwitterion.
hydrogen ion
the positively charged hydrogen atom (H+), present to excess in acid solutions.
ion pair
the pair of ions created when an atom has had an electron removed by ionizing radiation.
ion pump
see calcium pump, sodium pump.
ion trapping
a strategy for treatment of poisonings based on the principle that cell membranes are less permeable to ionized compounds. With knowledge of the characteristics of the toxin, treatment can be given to alter the acid-base balance in favor of ionization.