Hydrogen (redirected from Hydrogen bonding)

hydrogen /hy·dro·gen/ (H) (hi´dro-jen) chemical element, at. no. 1; it exists as the mass 1 isotope (protium, light or ordinary h.), mass 2 isotope (deuterium, heavy h.), and mass 3 isotope (tritium) .

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hydrogen cyanide  an extremely poisonous liquid or gas, HCN, used as a rodenticide and insecticide.

hydrogen peroxide  a strongly disinfectant cleansing and bleaching liquid, H2O2, used in dilute solution in water.

hydrogen sulfide  an ill-smelling, colorless, poisonous gas, H2S.

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hy·dro·gen (hdr-jn)

n. Symbol H

A colorless, highly flammable gaseous element, the most abundant in the universe, used in ammonia and methanol synthesis, in the hydrogenation of organic materials, and as a reducing atmosphere. Atomic number 1.

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Hydrogen

The simplest, most common element known in the universe. It is composed of a single electron (negatively charged particle) circling a nucleus consisting of a single proton (positively charged particle). It is the nuclear proton of hydrogen that makes MRI possible by reacting resonantly to radio waves while aligned in a magnetic field.

Mentioned in: Magnetic Resonance Imaging

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hydrogen (H),

n a gaseous, univalent element. Its atomic number is 1 and its atomic weight is 1.008. It is the simplest and lightest of the elements and is normally a colorless, odorless, highly flammable diatonic gas.

hydrogen peroxide,

n an unstable compound of hydrogen and oxygen that is easily broken down into water and oxygen. A 3% solution is used as a mild antiseptic for the skin and mucous membranes; more concentrated solutions may be used as a whitening (bleaching) agent. May be used to reduce gingival inflammation, but may not eliminate the responsible bacteria.

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hydrogen

a chemical element, atomic number 1, atomic weight 1.00797, symbol H. See Table 6. It exists as the mass 1 isotope (protium, or light or ordinary hydrogen), mass 2 isotope (deuterium, heavy hydrogen), and mass 3 isotope (tritium).

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hydrogen bonding

weak electrostatic attraction between one electronegative atom and the hydrogen atom covalently linked to a second electronegative atom.

hydrogen breath test

detects hydrogen production as a product of bacterial fermentation of carbohydrates, an indicator of inflammatory bowel disease or carbohydrate malabsorption.

hydrogen cyanide

hydrocyanic acid.

heavy hydrogen

hydrogen having double the mass of ordinary hydrogen; deuterium.

hydrogen ion balance

see acid-base balance.

hydrogen ion concentration

the degree of concentration of hydrogen ions (the acid element) in a solution. Its symbol is pH, and expresses the degree to which a solution is acidic or alkaline. The pH range extends from 0 to 14, pH 7 being neutral. A pH of less than 7 indicates acidity, above 7 indicates alkalinity. See also acid-base balance and ph.

hydrogen peroxide

H₂O₂, used in solution as an antibacterial agent. A 3% solution foams on touching skin or mucous membrane and appears to have a mechanical cleansing action.

hydrogen peroxide-based teat dips

see teat dip.

hydrogen sulfide

an ill-smelling, colorless, poisonous gas, H₂S; much used as a chemical reagent. Hydrogen sulfide is often present in gases from oil wells and from manure vats under slatted floor barns. Poisoning of cattle causes diarrhea, dehydration, dyspnea and death in convulsions. The feces are black and the breath smells of hydrogen sulfide. Called also hydrosulfuric acid. See also manure pit gas poisoning.

hydrogen swell

defective canned meat can. Can is distended due to production of hydrogen as a result of corrosion of the can surface.