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{{Unreferenced|date=December 2009}}
This is a preview for the new '''MathML rendering mode''' (with SVG fallback), which is availble in production for registered users.
[[Wilhelm Ostwald]]’s '''dilution law''' is a relationship between the [[dissociation constant]] and the degree of dissociation of a weak [[electrolyte]] ([[acid]]s, [[Base (chemistry)|base]]s).


:<math>\mathsf{K_p = \frac{c(K^+) \cdot c(A^-)}{c(KA)} = \frac{\alpha^2}{1-\alpha} \cdot c_0}</math>
If you would like use the '''MathML''' rendering mode, you need a wikipedia user account that can be registered here [[https://en.wikipedia.org/wiki/Special:UserLogin/signup]]
* Only registered users will be able to execute this rendering mode.
* Note: you need not enter a email address (nor any other private information). Please do not use a password that you use elsewhere.


where:
Registered users will be able to choose between the following three rendering modes:  
* K<sub>p</sub>: constant of protolysis
* α: degree of dissociation (or degree of protolysis)
* c(A<sup>-</sup>): concentrations of anions
* c(K<sup>+</sup>): concentration of cations
* c<sub>0</sub>: overall concentration
* c(KA): concentration of associated electrolyte.


Concerning conductivity, this results in the following relation:
'''MathML'''
:<math forcemathmode="mathml">E=mc^2</math>


<math>\frac{\Lambda_c^2}{(\Lambda_0 - \Lambda_c)\Lambda_0}\cdot c = K_c</math>
<!--'''PNG'''  (currently default in production)
According to Arrhenius theory of electrolyte dissociation, the molecules of an electrolyte in solution are constantly splitting up into ions and the ions are constantly reuniting to form unionized molecules. Therefore, a dynamic equilibrium exists between ions and unionized molecules of the electrolyte in solution. It was pointed out by Ostwald that like chemical equilibrium, law of mass action can be applied to such systems also.
:<math forcemathmode="png">E=mc^2</math>


Consider a binary electrolyte AB which dissociates into A+ and B- ions and the equilibrium state is represented by the equation:
'''source'''
:<math forcemathmode="source">E=mc^2</math> -->


<span style="color: red">Follow this [https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-rendering link] to change your Math rendering settings.</span> You can also add a [https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-rendering-skin Custom CSS] to force the MathML/SVG rendering or select different font families. See [https://www.mediawiki.org/wiki/Extension:Math#CSS_for_the_MathML_with_SVG_fallback_mode these examples].


==Demos==


                                AB ↔  A+ + B-
Here are some [https://commons.wikimedia.org/w/index.php?title=Special:ListFiles/Frederic.wang demos]:


        Initially t = o      C        0    0


        At equilibrium    C(1-α)  Cα    Cα
* accessibility:
** Safari + VoiceOver: [https://commons.wikimedia.org/wiki/File:VoiceOver-Mac-Safari.ogv video only], [[File:Voiceover-mathml-example-1.wav|thumb|Voiceover-mathml-example-1]], [[File:Voiceover-mathml-example-2.wav|thumb|Voiceover-mathml-example-2]], [[File:Voiceover-mathml-example-3.wav|thumb|Voiceover-mathml-example-3]], [[File:Voiceover-mathml-example-4.wav|thumb|Voiceover-mathml-example-4]], [[File:Voiceover-mathml-example-5.wav|thumb|Voiceover-mathml-example-5]], [[File:Voiceover-mathml-example-6.wav|thumb|Voiceover-mathml-example-6]], [[File:Voiceover-mathml-example-7.wav|thumb|Voiceover-mathml-example-7]]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-Audio-Windows7-InternetExplorer.ogg Internet Explorer + MathPlayer (audio)]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-SynchronizedHighlighting-WIndows7-InternetExplorer.png Internet Explorer + MathPlayer (synchronized highlighting)]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-Braille-Windows7-InternetExplorer.png Internet Explorer + MathPlayer (braille)]
** NVDA+MathPlayer: [[File:Nvda-mathml-example-1.wav|thumb|Nvda-mathml-example-1]], [[File:Nvda-mathml-example-2.wav|thumb|Nvda-mathml-example-2]], [[File:Nvda-mathml-example-3.wav|thumb|Nvda-mathml-example-3]], [[File:Nvda-mathml-example-4.wav|thumb|Nvda-mathml-example-4]], [[File:Nvda-mathml-example-5.wav|thumb|Nvda-mathml-example-5]], [[File:Nvda-mathml-example-6.wav|thumb|Nvda-mathml-example-6]], [[File:Nvda-mathml-example-7.wav|thumb|Nvda-mathml-example-7]].
** Orca: There is ongoing work, but no support at all at the moment [[File:Orca-mathml-example-1.wav|thumb|Orca-mathml-example-1]], [[File:Orca-mathml-example-2.wav|thumb|Orca-mathml-example-2]], [[File:Orca-mathml-example-3.wav|thumb|Orca-mathml-example-3]], [[File:Orca-mathml-example-4.wav|thumb|Orca-mathml-example-4]], [[File:Orca-mathml-example-5.wav|thumb|Orca-mathml-example-5]], [[File:Orca-mathml-example-6.wav|thumb|Orca-mathml-example-6]], [[File:Orca-mathml-example-7.wav|thumb|Orca-mathml-example-7]].
** From our testing, ChromeVox and JAWS are not able to read the formulas generated by the MathML mode.


So, dissociation constant may be given as
==Test pages ==


                K = [A+][B-]/[AB] = (Cα * Cα)/C(1-α)
To test the '''MathML''', '''PNG''', and '''source''' rendering modes, please go to one of the following test pages:
*[[Displaystyle]]
*[[MathAxisAlignment]]
*[[Styling]]
*[[Linebreaking]]
*[[Unique Ids]]
*[[Help:Formula]]


                  =  Cα2 /(1-α)                                        ....... (i)
*[[Inputtypes|Inputtypes (private Wikis only)]]
 
*[[Url2Image|Url2Image (private Wikis only)]]
 
==Bug reporting==
 
If you find any bugs, please report them at [https://bugzilla.wikimedia.org/enter_bug.cgi?product=MediaWiki%20extensions&component=Math&version=master&short_desc=Math-preview%20rendering%20problem Bugzilla], or write an email to math_bugs (at) ckurs (dot) de .
For very weak electrolytes,
 
                α <<< 1,  (1 - α ) = 1
 
      .·.                    K = Cα2
 
                              α = √K/C                            ....... (ii)
 
Concentration of any ion = Cα = √CK .
 
From equation (ii) it is a clear that degree of ionization increases on dilution.
 
 
 
Thus, degree of dissociation of a weak electrolyte is proportional to the square root of dilution.
 
 
Limitations of Ostwald's dilution law:
 
The law holds good only for weak electrolytes and fails completely in the case of strong electrolytes. The value of 'α' is determined by conductivity measurements by applying the formula Λ/Λ∞. The value of 'α' determined at various dilutions of an electrolyte when substituted in Eq. (i) gives a constant value of K only in the case of weak electrolytes like CH3COOH, NH4OH, etc. the cause of failure of Ostwald's dilution law in the case of strong electrolytes is due to the following factors"
 
(i)  The law is based on the fact that only a portion of the electrolyte is dissociated into ions at ordinary dilution and completely at infinite dilution. Strong electrolytes are almost completely ionized at all dilutions and Λ/Λ∞ does not give accurate value of 'α'.
 
(ii)  When concentration of the ions is very high, the presence of charges on the ions appreciably effects the equilibrium. Hence, law of mass action its simple form cannot be strictly applied in the case of strong electrolytes.
 
* K<sub>c</sub>: constant of dissociation
* <math>\Lambda_c</math>: equivalent conductivity
* <math>\Lambda_0</math>: boundary conductivity
* c: concentration of electrolyte.
==See also==
[[Autosolvolysis]]
{{DEFAULTSORT:Law Of Dilution}}
[[Category:Physical chemistry]]
[[Category:Enzyme kinetics]]
 
[[ca:Llei de dilució d'Ostwald]]
[[de:Ostwaldsches Verdünnungsgesetz]]
[[fr:Loi de dilution d'Ostwald]]
[[it:Legge di Ostwald]]
[[pl:Prawo rozcieńczeń Ostwalda]]
[[pt:Lei da diluição de Ostwald]]
[[ru:Закон разбавления Оствальда]]
[[sr:Оствалдов закон]]
[[uk:Закон розведення Освальда]]
[[zh:稀释定律]]

Latest revision as of 23:52, 15 September 2019

This is a preview for the new MathML rendering mode (with SVG fallback), which is availble in production for registered users.

If you would like use the MathML rendering mode, you need a wikipedia user account that can be registered here [[1]]

  • Only registered users will be able to execute this rendering mode.
  • Note: you need not enter a email address (nor any other private information). Please do not use a password that you use elsewhere.

Registered users will be able to choose between the following three rendering modes:

MathML


Follow this link to change your Math rendering settings. You can also add a Custom CSS to force the MathML/SVG rendering or select different font families. See these examples.

Demos

Here are some demos:


Test pages

To test the MathML, PNG, and source rendering modes, please go to one of the following test pages:

Bug reporting

If you find any bugs, please report them at Bugzilla, or write an email to math_bugs (at) ckurs (dot) de .

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