Question

what is the difference between conductivity and molar conductivity .also tell their units

Answer 1

Basically there is No difference between molar conductance and conductivity.

Definition wise the Difference is "Conductance is constant for a particular electrolyte(only when same volume of solvent, say 1000mL is considered), because it takes into consideration of dissociation of 1gram Mole of electrolyte.And Conductivity takes into account of the Molar concentration (May or may not be 1gram Mole) of electrolyte.

Molar conductivity is a generalised definition,

which is defined as the "conductivity of an electrolyte solution divided by the molar concentration of the electrolyte"

so measures the efficiency with which a given electrolyte conducts electricity in solution.

Its units are siemens per meter per molarity, or siemens meter-squared per mole. The usual symbol is a capital lambda, Λ, or Λm.


 

The molar conductance is defined as the conductance of all the ions produced by ionization of 1 g mole of an electrolyte when present in V (volume should be in mL )mLof solution. It is denoted by .


Molar conductance     μ
   
 So,As Dissociation increases with dilution, Molar Conductance increases.

Hence Molar conductance ID directly proportional to Volume V 
  
Hence,Molar conductance     μ = k ×V
Where,k is the constant.                                 

where V is the volume in mL containing 1 g mole of the electrolyte. 

If c is the concentration of the solution in g mole per litre, then


                        μ  = k ×  1000/c

                It units are ohm-1 cm2 mol-1