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

When an electron revolves in a stationary orbit then, When an electron revo...

When an electron revolves in a stationary orbit then: (1) It absorbs energy (2) It emits radiation (3) Its energy remains constant (4 )It gains kinetic energy Ans:

What are the disadvantages of cold working, What are the Disadvantages of c...

What are the Disadvantages of cold working (i) Higher forces are required for deformation. (ii) Heavier and more powerful equipment is required. (iii) May produce undesir

What is function group, An atom or group of atoms, which verify the charact...

An atom or group of atoms, which verify the characteristic properties of the Substance it, is known as functional group.

Enzyme .., what clinical enzymes of medicine?

what clinical enzymes of medicine?

Pulak, why uranium235 and thorium232 dont participate in nuclear fission

why uranium235 and thorium232 dont participate in nuclear fission

Cyanohydrin .., industrial application of cyanohydrin.?

industrial application of cyanohydrin.?

Reverse hyperconjugation, Reverse Hyperconjugation : The method of hyper...

Reverse Hyperconjugation : The method of hyperconjugation is as well observed in the system given below, In such type of system the effect operates in the opposite direc

What are polymers, A substance that has a molecular structure built up chi...

A substance that has a molecular structure built up chiefly or completely from a large number of similar units bonded together.

What do you understand by miller indices of a crystal plane, What do you un...

What do you understand by Miller indices of a crystal plane? Miller Indices are a symbolic vector representation for the orientation of an atomic plane in a crystal lattice an

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