enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. pH - Wikipedia

    en.wikipedia.org/wiki/PH

    The pH range is commonly given as zero to 14, but a pH value can be less than 0 for very concentrated strong acids or greater than 14 for very concentrated strong bases. [2] The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. [3]

  3. Acidity function - Wikipedia

    en.wikipedia.org/wiki/Acidity_function

    Non-nucleophilic. Weak. v. t. e. An acidity function is a measure of the acidity of a medium or solvent system, [ 1][ 2] usually expressed in terms of its ability to donate protons to (or accept protons from) a solute ( Brønsted acidity ). The pH scale is by far the most commonly used acidity function, and is ideal for dilute aqueous solutions.

  4. Universal indicator - Wikipedia

    en.wikipedia.org/wiki/Universal_indicator

    Universal indicator. A universal indicator is a pH indicator made of a solution of several compounds that exhibit various smooth colour changes over a wide range pH values to indicate the acidity or alkalinity of solutions. A universal indicator can be in paper form or present in a form of a solution. [1]

  5. pH indicator - Wikipedia

    en.wikipedia.org/wiki/PH_indicator

    A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. [1] Hence, a pH indicator is a chemical detector for hydronium ions (H 3 O +) or hydrogen ions (H +) in the ...

  6. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    v. t. e. In chemistry, an acid dissociation constant (also known as acidity constant, or acid-ionization constant; denoted ⁠ ⁠) is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction. known as dissociation in the context of acid–base reactions. The chemical species HA is an ...

  7. pH meter - Wikipedia

    en.wikipedia.org/wiki/PH_meter

    Beckman model 72 pH meter, 1960. 781 pH/Ion Meter pH meter by Metrohm. A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH. [2] The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode ...

  8. Hammett acidity function - Wikipedia

    en.wikipedia.org/wiki/Hammett_acidity_function

    The Hammett acidity function (H 0) is a measure of acidity that is used for very concentrated solutions of strong acids, including superacids.It was proposed by the physical organic chemist Louis Plack Hammett [1] [2] and is the best-known acidity function used to extend the measure of Brønsted–Lowry acidity beyond the dilute aqueous solutions for which the pH scale is useful.

  9. Soil pH - Wikipedia

    en.wikipedia.org/wiki/Soil_pH

    Soil pH is a measure of the acidity or basicity (alkalinity) of a soil. Soil pH is a key characteristic that can be used to make informative analysis both qualitative and quantitatively regarding soil characteristics. [1] pH is defined as the negative logarithm (base 10) of the activity of hydronium ions (H+.