hydrogen ion concentration


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concentration

 [kon″sen-tra´shun]
1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.
3. intense mental focus.
hydrogen ion concentration see hydrogen ion concentration.
mass concentration the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/l).
mean corpuscular hemoglobin concentration (MCHC) the average hemoglobin concentration in erythrocytes, conventionally expressed in “per cent,” meaning grams per deciliter of red blood cells, obtained by dividing the blood hemoglobin concentration (in g/dl) by the hematocrit (in l/l): MCHC = Hb/Hct.
minimal alveolar concentration (MAC) the concentration of anesthetic that at a pressure of 1 atmosphere produces immobility in 50 per cent of subjects exposed to a noxious stimulus.
minimal bactericidal concentration (MBC) the lowest concentration of a given antibiotic required to kill a specific organism.
minimal inhibitory concentration (MIC) the lowest concentration of a given antibiotic that inhibits the growth of a specific organism.
molar concentration the concentration of a substance expressed in terms of molarity.
concentration test a test of renal function based on the patient's ability to concentrate urine; see also fishberg concentration test.

hydrogen

 (H) [hi´dro-jen]
a chemical element, atomic number 1, atomic weight 1.00797. (See Appendix 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).
hydrogen cyanide an extremely poisonous colorless liquid or gas, HCN, a decomposition product of various naturally occurring glycosides and a common cause of cyanide poisoning. Inhalation of the gas can cause death within a minute. Called also hydrocyanic acid.
heavy hydrogen deuterium.
hydrogen ion concentration the degree of concentration of hydrogen ions (the acid element) in a solution. Its symbol is pH, and it 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 indicating acidity, and one above 7 indicating alkalinity. See also acid-base balance.
hydrogen peroxide H2O2, an antiseptic with a mildly antibacterial action. A 3 per cent solution foams on touching skin or mucous membrane and appears to have a mechanical cleansing action.
hydrogen sulfide H2S, a poisonous gas with an offensive smell, released from decaying organic material, natural gas, petroleum, and sulfur deposits, and sometimes used as a chemical reagent.

hydrogen ion concentration

The number of free hydrogen ions in a given quantity of fluid, such as blood. Hydrogen ion concentration (pH) determines acidity. In the blood it must be kept within the narrow limits of pH 7.37–7.45 or a fatal condition occurs.

hydrogen ion concentration

see PH.

concentration

1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.

hydrogen ion concentration
an expression of the degree of acidity or alkalinity (pH) of a solution. See also acid-base balance.
mass concentration
the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/l).
minimum effective concentration
the threshold level of a drug in plasma below which the efficiency of the drug as a treatment drops off sharply.
molar concentration
the amount of a constituent in moles (millimoles or micromoles) divided by the volume of the mixture, as millimoles per liter (mmol/l).
concentration test
a test of renal function based on the patient's ability to concentrate urine. See water deprivation test.

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).

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
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
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.
References in periodicals archive ?
Hydrogen ion concentration (pH) values (Table 5) slightly increased more in the Kilishi stored in the refrigerator than Kilishi stored at ambient temperature probably due to protein degrading microorganisms such as Pseudomonas that predominates at low temperature.