en>Wtshymanski: ce; redundant, merge single sentences to paragraph

2015-01-01T21:00:49Z

ce; redundant, merge single sentences to paragraph

← Older revision		Revision as of 23:00, 1 January 2015
Line 1:		Line 1:
	'~~''Molar conductivity''' is defined~~ as the [[Conductivity (electrolytic)\|conductivity]] of an [[electrolyte]] [[solution]] divided by the [[molar concentration]] of the electrolyte, and so measures the efficiency with which a given electrolyte conducts electricity in solution. Its units are [[Siemens (unit)\|siemens]] per meter per [[molarity]], or siemens meter-squared per mole. ~~The usual symbol~~ is ~~a capital lambda, Λ, or Λ<sub>m</sub>.~~		Nice to meet you, my title is Figures Held though I don't really like being known as like that. What I adore doing is taking part in baseball over the counter std test but I haven't made a dime with it. Puerto Rico is [http://www.buzzbit.net/user/AFilson home std test kit] exactly [http://www.gaysphere.net/blog/167593 at home std test] home [http://home-Hiv-Tests.com/home-test-kits/std-tests std testing] where he's always been living but she requirements to move simply because of her family. For years I've been operating as a [http://Intheknowpeel.ca/stiaids/list.htm payroll clerk].<br><br>my web blog :: [http://www.eddysadventurestore.nl/nieuws/eliminate-candida-one-these-tips home std test]

	~~== History ==~~

	~~[[Friedrich Kohlrausch]] established that to a high accuracy~~ in ~~dilute solutions, molar conductivity is composed of individual contributions of ions. This is known as~~ the '~~'law of independent migration of ions''~~.~~<ref>Castellan, G~~.W. ~~''Physical Chemistry''. Benjamin~~/~~Cummings, 1983.<~~/~~ref>~~

	~~== Description ==~~

	~~From its definition, the molar conductivity is given by~~:~~<ref>''The best test preparation for the GRE Graduate Record Examination Chemistry Test~~.~~'' Published by the Research and Education Association, 2000, ISBN 0-8789-600-8. p. 149~~.</~~ref>~~

	~~:<math>\Lambda_{\mathrm{m}} = \frac{\kappa}{c}<~~/~~math>~~

	~~where:~~
	* κ is the measured conductivity
	* ''c'' is the electrolyte concentration.

	~~Two cases should be distinguished: strong electrolytes and weak electrolytes.~~

	~~For [[strong electrolyte]~~]~~s, such as~~ [[salt]]s, [[strong acid]]s and [[strong base]]s, the molar conductivity depends only ''weakly'' on concentration. Based on experimental data [[Friedrich Kohlrausch]] (around the year 1900) proposed the non-linear law for strong electrolytes:

	~~:<math>\Lambda_{\mathrm{m}} =\Lambda_{\mathrm{m}}^\circ - K\sqrt{c}<~~/~~math>~~

	~~where~~
	* <math>\Lambda_{\mathrm{m}}^\circ</~~math> is the molar conductivity at infinite dilution (or ''limiting molar conductivity'')~~
	* ''K'' is the Kohlrausch coefficient, which depends mainly on the stoichiometry of the specific salt in solution.
	~~This law is valid for low electrolyte concentrations only; it fits into the [[Debye~~-~~Hückel~~-~~Onsager equation]] :~~.~~<ref>{{cite book\|last=Atkins\|first=P. W.\|title=The Elements of Physical Chemistry\|publisher=Oxford University Press\|year=2001\|isbn=0~~-19-~~879290~~-~~5}}</ref>~~

	~~For weak electrolytes (i.e. incompletely dissociated electrolytes), however, the molar conductivity~~ '~~'strongly'' depends on concentration: The more dilute a solution, the greater its ''molar'' conductivity, due~~ to ~~increased [[ionic dissociation]]. (This, for example, is the case~~ of ~~SDS-coated proteins in the stacking gel of an [[SDS-PAGE]]~~.)

	~~The limiting molar conductivity can be decomposed into contributions from the different ions (Kohlrausch~~'~~s law of independent migration of ions):~~

	:~~<math>\Lambda_{\mathrm{m}}^\circ = \Sigma_i \nu_i \lambda_i<~~/~~math>~~

	~~where:~~
	* <math>\lambda_i</~~math> is the molar ionic conductivity of ion ''i''~~.
	* <math>\nu_i</~~math> is the number of ions ''i'' in the formula unit of the electrolyte (e.g. 2 and 1 for Na<sup>+</sup> and SO<sub>4</sub><sup>2-</sup> in Na<sub>2<~~/~~sub>SO<sub>4</sub>)~~

	~~== Applications ==~~
	~~[[Law of dilution\|Ostwald's law of dilution]], which gives the dissociation constant of a weak electrolyte as a function of concentration, can be written in terms of molar conductivity~~. ~~Thus, the [[pKa~~]~~] values of acids can be calculated by measuring the molar conductivity and extrapolating into zero concentration~~. ~~Namely, pK~~<~~sub~~>a<~~/sub~~> ~~= p(K/(1 mol dm<sup>−3</sup>)) at the zero-concentration limit, where K is the dissociation constant from Ostwald's law.~~

	~~==References==~~
	~~<references />~~

	[http://www.~~iupac~~.~~org~~/~~publications~~/~~pac/pdf/1994/pdf/6608x1739.pdf]~~

	~~[[Category:Electrochemistry]]~~
	~~[[Category:Physical chemistry]~~]

89.168.132.115: Corrected grammar

2014-01-22T20:12:07Z

Corrected grammar

Show changes

87.242.53.129: /* External links */

2012-08-30T14:21:37Z

External links

Show changes

Induction generator - Revision history

en>Wtshymanski: ce; redundant, merge single sentences to paragraph

89.168.132.115: Corrected grammar

87.242.53.129: /* External links */