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pH
pH, range of numbers expressing the relative acidity or alkalinity of a solution. In general, pH values range from 0 to 14. The pH of a neutral solution, i.e., one which is neither acidic nor alkaline, is 7. Acidic solutions have pH values below 7; alkaline, or basic, solutions have pH values above 7. A pH value provides a measure of the hydrogen ion concentration of a solution. In pure water the concentration of hydrogen ions is equal to 0.0000001, or 10−7, moles per liter. (A mole is the amount of a substance, expressed in grams, that is equal to the molecular weight, or formula weight, of the substance.) When an acid is added to pure water, the hydrogen ion concentration increases above this level. When an alkaline substance, or base, is added to pure water, the hydrogen ion concentration decreases below this level. Once the concentration is determined, the pH value is found by taking the exponent used in expressing this concentration and reversing its sign. This is expressed as pH=−log10 [H+]. For example, if the hydrogen ion concentration of a solution is 10−4, or 0.0001, moles per liter, the pH is 4. See indicators, acid-baseindicators, acid-base,
organic compounds that, in aqueous solution, exhibit color changes indicative of the acidity or basicity of the solution. Common indicators include p-nitrophenol, which is colorless from pH 1 to 5 and yellow from p
..... Click the link for more information. .pH[pē′āch] (chemistry) A term used to describe the hydrogen-ion activity of a system; it is equal to -log aH+; here aH+is the activity of the hydrogen ion; in dilute solution, activity is essentially equal to concentration and pH is defined as -log10[H+], where H+is hydrogen-ion concentration in moles per liter; a solution of pH 0 to 7 is acid, pH of 7 is neutral, pH over 7 to 14 is alkaline.
pH(S) (analytical chemistry) pH standard pHA measure of the acidity or alkalinity of a solution; numerically equal to 7.0 for a neutral solution; the pH value increases with increasing alkalinity and decreases with increasing acidity. Also See pH value.
PH1. On drawings, abbr. for phase. 2. Abbr. for phillips head.
photA unit of illumination equal to 1 lumen per square centimeter. Abbr. ph.pH potential of hydrogen; a measure of the acidity or alkalinity of a solution equal to the common logarithm of the reciprocal of the concentration of hydrogen ions in moles per cubic decimetre of solution. Pure water has a pH of 7, acid solutions have a pH less than 7, and alkaline solutions a pH greater than 7 PH (tool)The tool for looking up people in Eudora on theMacintosh. Equivalent to Unix's finger service.pH (2)Parallel Haskellph (networking)The country code for the Philippines.pH
pH the negative logarithm of the hydrogen ion concentration, [H+], a measure of the degree to which a solution is acidic or alkaline. An acid" >acid is a substance that can give up a hydrogen ion (H+); a base" >base is a substance that can accept H+. The more acidic a solution the greater the hydrogen ion concentration and the lower the pH; a pH of 7.0 indicates neutrality, a pH of less than 7 indicates acidity, and a pH of more than 7 indicates alkalinity. The pH is used as a measure of whether the body is maintaining a normal acid-base balance. A favorable pH is essential to the functioning of enzymes and other biochemical systems. The body's fluids are normally somewhat alkaline, the pH being between 7.35 and 7.45. A pH above 7.8 or below 6.8 is generally fatal. See also acidosis and alkalosis. pH scale. From Applegate, 2000.PhSymbol for phenyl.
pHSymbol for the negative decadic logarithm of the H+ ion concentration (measured in moles per liter); a solution with pH 7.00 (1 × 10-7 g molecular weight of H+K per liter) is neutral at 22°C (that is, [H+] = [OH-]), one with a pH value of more than 7.00 is alkaline, one with a pH lower than 7.00 is acid. At 37°C, neutrality is at a pH value of 6.80. Compare: dissociation constant of water. [p (power or potency) of [H+ ]] PHabbr.1. penthouse2. public health3. Purple HeartPH Abbreviation for:
acidity (pH)
hydrogen ion concentration
papillary hyperplasia
parathyroid hormone
partial hysterectomy
passive haemagglutination
past history
patient history
peliosis hepatis
phaeochromocytoma
pharmacy
phenacetin
Philadelphia
phosphate
pin hole
porphyria hepatica
posterior hypothalamus
postural hypotension
primary hyperparathyroidism
prolyl hydroxylase
Prospect Hill
pseudoepitheliomatous hyperplasia
public health
pulmonary haemorrhage
pulmonary haemosiderosis
pulmonary hypertensionstorage lesion Transfusion medicine The constellation of changes occurring in a unit of packed red cells during storage. See Red cell preservatives. Storage lesions ↑ Ammonium to 470 µmol/L–US: 800 µg/dL ↑ Free Hb in plasma from 82 to 6580 mg/L–US: 8.2 to 658 mg/dL ↑ K+ from 4.2 to 78.5 mmol/L–US: 4.2 to 78.5 mEq/L ↓ ATP from 100% to 45% ↓ 2,3 DPG to < 10% of original levels–replenished within 24 hours of transfusion ↓ Labile proteins, eg complement, fibronectin and coagulation factors ↓ to negligible ↓ Na+ from 169 to 111 mmol/L–US: 169 to 111 mEq/L ↓ pH from 7.6 to 6.7 Adverse physiologic effects of stored blood is negligible in the absence of a previous compromise of the Pt's–recipient's status Ph Abbreviation for phenyl.
pH Symbol for the negative logarithm of the H+ ion concentration (measured in moles per liter); a solution with pH 7.00 is neutral at 22°C, one with a pH of more than 7.0 is alkaline, and one with a pH lower than 7.00 is acid. At a temperature of 37°C, neutrality is at a pH value of 6.8. [p (power or potency) of [H+]]Ph1. Pharmacopoeia.2. Symbol for phenyl.
 pH SCALE: Values of body fluids and some familiar solutionspH [Ger. Potenz, power + H, symbol for hydrogen] In chemistry, a measure of the hydrogen ion concentration of a solution. The degree of acidity or alkalinity of a substance is expressed in a pH value. A solution that is neither acid nor alkaline has a pH of 7. Increasing acidity is expressed as a number less than 7, and increasing alkalinity as a number greater than 7. Maximum acidity is pH 0 and maximum alkalinity is pH 14. Because the pH scale is logarithmic, there is a 10-fold difference between each unit. For example, pH 5 is 10 times as acid as pH 6 and pH 4 is 100 times as acid as pH 6. The general mathematical formula defining pH is: pH = -log [H+], in which pH is the negative logarithm of the hydrogen ion concentration. The pH of a solution may be determined electrically by a pH meter or colorimetrically by the use of indicators. A list of indicators and the pH range registered by each is given under the indicator. See: illustration; table; indicator| Material | pH |
|---|
| 10% HCl | 1.0 | | Gastric juice | 1.0–5.0 | | 0.1% HCl | 3.0 | | Pure water (neutral) at 25°C | 7.0 | | Blood plasma | 7.35–7.45 | | Pancreatic juice | 8.4–8.9 | | 0.1% NaOH | 11.0 | | 10% NaOH | 13.0 | HCl—hydrochloric acid; NaOH—sodium hydroxide
pH An expression, widely used in medicine, of the acidity or alkalinity of a solution. pH is the logarithm to the base 10 of the concentration of free hydrogen ions in moles per litre, expressed as a positive number. The pH scale ranges from 0 to 14. Neutrality is 7. Figures below 7 indicate acidity, increasing towards zero; figures rising above 7 indicate increasing alkalinity. The pH of body fluids, in health, is accurately maintained between about 7.3 to 7.5. Below this range the condition of acidosis exists; above it, alkalosis. Both are dangerous.pH a measure of the hydrogen ion concentration in an aqueous solution. The formula is:  The formula produces a value in which the higher the number of H+ ions the lower the pH reading. The scale of pH values is from 1.0 (highly acid) to 14 (highly alkaline) with 7.0 as the neutral point. Since the pH is logarithmic, each change of one pH unit means a tenfold change in the number of hydrogen ions. pH can be measured by using indicators which change colour with changing pH, or by electrical means using a pH meter. pHA measurement of the acidity or alkalinity of a solution based on the amount of hydrogen ions available. Based on a scale of 14, a pH of 7.0 is neutral. A pH below 7.0 is an acid; the lower the number, the stronger the acid. A pH above 7.0 is a base; the higher the number, the stronger the base. Blood pH is slightly alkaline (basic) with a normal range of 7.36-7.44.Mentioned in: Blood Gas Analysis, Carbon Monoxide Poisoning, Hypokalemia, Metabolic Acidosis, Metabolic Alkalosis, Respiratory Acidosis, Respiratory Alkalosis, Sitz Bath, Urinalysis, Urinary Anti-InfectivespH Symbol for the logarithm to base 10 of the reciprocal of the hydrogen (H) ion concentration measured in gram molecular weight in an aqueous solution. A solution with a pH 7.0 is neutral, one with a pH of more than 7.0 is alkaline, one with a pH lower than 7.0 is acid. It is a convenient way of expressing the acidity or alkalinity of solutions, particularly of contact lens buffer solutions. Alkaline ophthalmic solutions generally cause less discomfort than acidic ones. Note: pH stands for power (or potency) of H. See acidosis.PH
PHThe two-character ISO 3166 country code for PHILIPPINES.PH
| Acronym | Definition |
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| PH➣Telephone | | PH➣Philippines (Internet top level domain) | | PH➣Public House | | PH➣Potential of Hydrogen - negative 10-base log (power) of the positive hydrogen ion concentration; measure of acidity | | PH➣Public Health | | PH➣Human Performance | | PH➣Phase | | PH➣Physical (layer, ISDN) | | PH➣Population Health | | PH➣Penthouse | | PH➣Please Help | | PH➣Pantyhose | | PH➣Photograph | | PH➣Paris Hilton | | PH➣Pearl Harbor | | PH➣Perth (postcode, United Kingdom) | | PH➣Personal Hygiene | | PH➣Pulmonary Hypertension | | PH➣Public Holiday | | PH➣Perpetual Help (Catholic schools) | | PH➣Philadelphia Chromosome (molecular biology) | | PH➣Purple Heart | | PH➣People Here (chat) | | PH➣Parliament House (various locations) | | PH➣Phosphates | | PH➣Pizza Hut | | PH➣Pennsylvania Hospital | | PH➣Phenyl | | PH➣Photocopy | | PH➣Phot (unit of illumination) | | PH➣Port Harcourt | | PH➣Pranic Healing | | PH➣Pandora Hearts (anime) | | PH➣Pädagogische Hochschule (German: University on Education) | | PH➣Physically Handicapped | | PH➣Pin Hole | | PH➣Parathyroid Hormone | | PH➣pubic hair | | PH➣Pulmonary Hemorrhage | | PH➣Providence Hospital | | PH➣Pleckstrin Homology | | PH➣Precipitation Hardening (steel) | | PH➣Place Holder (gaming) | | PH➣Professional Hunter | | PH➣Phantom Hourglass (Zelda game) | | PH➣Policyholder (insurance) | | PH➣Parker Hannifin Corporation | | PH➣Past Medical History | | PH➣Potato Head (toy) | | PH➣Potencial Hidrógeno (Spanish: Potential Hydrogen) | | PH➣Peak Hour | | PH➣Proportional Hazard(s) | | PH➣Purpura Hemorrhagica (horses) | | PH➣Partial Hepatectomy | | PH➣Phillips Head (screwdriver) | | PH➣Peace Health | | PH➣Partido Humanista (Portugese: Humanist Party) | | PH➣phenylalanine hydroxylase | | PH➣Paid Holiday | | PH➣Pilot House | | PH➣Portola Hills (California) | | PH➣Packet Header | | PH➣Porter Hall | | PH➣Player's Handbook (Dungeons & Dragons) | | PH➣Pharmacie Hospitalière (French: Hospital Pharmacy) | | PH➣Pablo Honey (Radiohead album) | | PH➣Pyramid Head (Silent Hill video game/movie) | | PH➣Personal Holiday | | PH➣Package Handler | | PH➣Pondus Hydrogenii (Latin: Hydrogen Weight) | | PH➣Personal Historian | | PH➣Phase Type Distribution (probability concept) | | PH➣Protocol Handlers | | PH➣Packet Handler | | PH➣Path History | | PH➣Paul Heyman (former WWE Smackdown GM) | | PH➣Potentia Hydrogenii (Latin: hydrogen power) | | PH➣Poo Head | | PH➣Probability of Hit | | PH➣Product Hierarchy | | PH➣Prahova County (Romania) | | PH➣Pinch Harmonic (Guitar sound made by pinching the strings with the pick) | | PH➣Pizza Haven (Seattle, WA; est. 1958) | | PH➣Pillowhead (gaming clan) | | PH➣Parity High | | PH➣Premium History (insurance) | | PH➣Presentation Header (TMN) | | PH➣Plataforma Humanista | | PH➣Physical Header | | PH➣Primal Heuristic (algorithm) | | PH➣Porphyric Hemophilia (disease) | | PH➣Phalasteen.com (website) | | PH➣Puissance de Hydrogen (French: power of hydrogen) | | PH➣Protection and Handset | | PH➣Poké Hunters (webcomic) | | PH➣(USN Rating) Photographer's Mate |
pH
Synonyms for pHnoun (from potential of Hydrogen) the logarithm of the reciprocal of hydrogen-ion concentration in gram atoms per literSynonymsRelated Words- hydrogen ion concentration
- acidity
- alkalinity
- neutrality
- chemical science
- chemistry
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