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

What is stoichiometry, Q. What is Stoichiometry? Ans. As you know ...

Q. What is Stoichiometry? Ans. As you know a chemical equation is like a recipe. Each of the different ingredients combine in certain ratios to form the end product. The

Show reduction to metals, Q. Show Reduction to Metals? After removed of...

Q. Show Reduction to Metals? After removed of the gangue, i.e. impurities physically mixed with the metal elements, the concentrated ore becomes ready for the isolation of meta

Define why the glocose and fructose form the same osazone, Glucose and fruc...

Glucose and fructose are epimers so they are differ in their second carbon position and remaining is same so when they react with phenylhydrazeen they give same osazone

The statements, The statements: (1)  In filling a group of orbitals of equ...

The statements: (1)  In filling a group of orbitals of equal energy, it is energetically preferable to assign electrons to empty orbitals rather than pair them into a particular o

Molar concentration of a saturated solution, The K sp of the phosphate fer...

The K sp of the phosphate fertilizer CaHPO 4 .2 H2O is 2.7 x 10 -7 at 25 o C.  What is the molar concentration of a saturated solution?  What mass of this compound will dissolve

Raising heavy weights by water pressure, Raising heavy weights by water pre...

Raising heavy weights by water pressure Get a rubber hot-water bottle. Put a one- hole stopper carrying a short glass tube tightly in the neck. Punch a hole in the bottom of a

What is a mixture experiment, Q. What is a mixture experiment? Mixture ...

Q. What is a mixture experiment? Mixture experiment is an experiment in which food quality indices are assured to depend on the relative proportion of ingredients.

Bond order of li(2)(minus) anion molecule, What is the Bond Order of Li(2)(...

What is the Bond Order of Li(2)(minus) anion molecule?  Ans) No. of bonding elecrtons =3 (valence), anti bonding =0 (given its state) thus =bond order =3/2=1.2

Explain about magnetic separation, Q. Explain about Magnetic Separation ? ...

Q. Explain about Magnetic Separation ? This process is based on the difference in magnetic properties of minerals. If the ore but not the gangue is attracted by a magnetic fiel

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