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  2. pH - Wikipedia

    en.wikipedia.org/wiki/PH

    Pure water has a pH of 7 at 25°C, meaning it is neutral. When an acid is dissolved in water, the pH will be less than 7, while a base, or alkali, will have a pH greater than 7. A strong acid, such as hydrochloric acid, at concentration 1 mol dm −3 has a pH of 0, while a strong alkali like sodium hydroxide, at the same concentration, has a pH ...

  3. Henderson–Hasselbalch equation - Wikipedia

    en.wikipedia.org/wiki/Henderson–Hasselbalch...

    The Henderson–Hasselbalch equation can be used to model these equilibria. It is important to maintain this pH of 7.4 to ensure enzymes are able to work optimally. [10] Life threatening Acidosis (a low blood pH resulting in nausea, headaches, and even coma, and convulsions) is due to a lack of functioning of enzymes at a low pH. [10]

  4. Acid strength - Wikipedia

    en.wikipedia.org/wiki/Acid_strength

    When the acidic medium in question is a dilute aqueous solution, the is approximately equal to the pH value, which is a negative logarithm of the concentration of aqueous + in solution. The pH of a simple solution of an acid in water is determined by both K a {\displaystyle K_{{\ce {a}}}} and the acid concentration.

  5. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    Express each concentration value as the ratio c/c 0, where c 0 is the concentration in a [hypothetical] standard state, with a numerical value of 1, by definition. [19] Express the concentrations on the mole fraction scale. Since mole fraction has no dimension, the quotient of concentrations will, by definition, be a pure number.

  6. Acid value - Wikipedia

    en.wikipedia.org/wiki/Acid_value

    In chemistry, acid value (AV, acid number, neutralization number or acidity) is a number used to quantify the acidity of a given chemical substance. It is the quantity of base (usually potassium hydroxide (KOH)), expressed as milligrams of KOH required to neutralize the acidic constituents in 1 gram of a sample.

  7. Standard state - Wikipedia

    en.wikipedia.org/wiki/Standard_state

    The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.A degree sign (°) or a superscript Plimsoll symbol (⦵) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (ΔH°), change in entropy (ΔS°), or change in Gibbs free energy (ΔG°).

  8. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    In chemistry, the rate equation (also known as the rate law or empirical differential rate equation) is an empirical differential mathematical expression for the reaction rate of a given reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only. [1]

  9. Hammett acidity function - Wikipedia

    en.wikipedia.org/wiki/Hammett_acidity_function

    On this scale, pure H 2 SO 4 (18.4 M) has a H 0 value of −12, and pyrosulfuric acid has H 0 ~ −15. [7] Take note that the Hammett acidity function clearly avoids water in its equation. It is a generalization of the pH scale—in a dilute aqueous solution (where B is H 2 O), pH is very nearly equal to H 0 .