Saturday, February 2, 2008

IIT JEE Revision - Electrochemistry - Molar Conductance

Electrolytic conductance, specific, equivalent and molar conductance,


Electrolytic conductance

The flow of electric current through an electrolytic solution is known as electrolytic conduction.

Electrolytic conduction also follows Ohm's law.

V = I/R

R = ρ* l/a

ρ is called specific resistance.
The reciprocal of specific resistance is termed specific conductance. It may be defined as the conductance of a solution of 1 cm length and having 1 sq.cm as the area of cross section.

Specific conductance is the conductance of one centimetre cube of a solution of an electrolyte. It is denoted by k (kappa)

κ = 1/ρ

The equivalent conductivity of an electrolyte may be defined as the conductance of a volume of solution containing one equivalent mass of a dissolved substance when placed between two parallel electrodes which are at a unit distance apart, and large enough to contain between them the whole solution.

The molar conductivity of a solution gives the conducting power of ions produced by one molar mass of an electrolyte at any particular concentration.

It is denoted by Λm (Lambda).

Λm = κ/M

where M is the molar concentration

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