Ion mobility, Chemistry

Assignment Help:

Ion mobility:

Ion mobility is related to molar conductivity by the equations:

723_ion mobolity.png

which allows the mobilities, u+ and u- of the cation and anion to be determined from molar conductivity measurements at and away from infinite dilution. z+ and z- are the formal charges of the cation and anion respectively, so z+F and |z-F| are the magnitudes of the charges on a mole of cations and anions. The mobility is always positive (+) and is a measure of the terminal migration speed of an ion per unit applied electric field. This limiting speed is accelerating due to the field is exactly balanced by the viscous drag of the ions moving through the solution which for a spherical ions lead to the equations:

55_ion mobolity1.png

where e is the charge on the electron (-), so ze is the charge on the ions, η is the viscosity, a constant for any solvents which determines how easy it is for the ion to part the solvent molecule and move through solution and a is the hydrodynamic radius of the solvated ion.

 

H+/OH- mobility:

Hydroxide and Protons ions have anomalously high ionic molar conductivities and mobilities in comparison to all ions, and in particular for their size. That is as a result of the mechanism by which they move through solution, called the Grotthus mechanism (Fig. 1).

 

2320_ion mobolity2.png

Fig. 1. The Grotthus mechanism for (a) H+; (b) OH- ion motion in water. The arrows indicate the concerted proton movement when the field is applied.


Related Discussions:- Ion mobility

Maximum number of electrons present in n, Maximum number of electrons prese...

Maximum number of electrons present in N  shell is: (1) 18              (2) 32        (3) 2              (4) 8 Ans: 32

DSC- TGA, i have a thermogram of magnesium oxalate and have to determine th...

i have a thermogram of magnesium oxalate and have to determine the mass lost in each step. And also calculate the number of water of hydration for each oxalate hydrate .

Illustrate the descriptive analysis of sensory method, Q. Illustrate the de...

Q. Illustrate the descriptive analysis of Sensory method? Sensory methods may be used to quantify the perceived intensities of the sensory attributes of a product. The quantif

Illustrate structure of the water molecule, Q. Illustrate Structure of the ...

Q. Illustrate Structure of the Water Molecule? Ans. A water molecule is composed of two hydrogen atoms and one oxygen atom covalently bonded together. The following anim

Electro affinity.., which factor on electron affinity depend?

which factor on electron affinity depend?

Define the citrus fruits product, Citrus Fruits A large number of con...

Citrus Fruits A large number of constituents in citrus products have been shown to be capable of preventing or alleviating diseases and promoting health. Vitamin C, E, and car

Calculate the value of the rydberg constant, Positronium consists of an ele...

Positronium consists of an electron and a positron (a particle which has the same mass as an electron, but opposite charge) orbiting round their common centre of mass. Calculate th

Separation of alkane, Separation of alkane, alkene and alkyne  The gase...

Separation of alkane, alkene and alkyne  The gaseous mixture is passed via ammonical cuprous chloride solution. The alkyne (acetylene) reacts along with   and makes a red preci

Calculate the stoichiometric ratio, Consider 1:1 stoichiometric polymerisat...

Consider 1:1 stoichiometric polymerisation of 1, 4-diaminobutane with sebacoyl chloride. (a) Write down a balanced chemical equation for the polymerization (b) Name the polym

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd