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Question

Question: What is the relationship between degree of dissociation and molar conductivity?...

What is the relationship between degree of dissociation and molar conductivity?

Explanation

Solution

We need to remember that the molar conductivity of an electrolyte is defined as its conductivity divided by its molar concentration. There are two types of electrolytes: strong and weak. Strong electrolytes usually undergo complete ionization, due to which they have higher conductivity than weak electrolytes, which leads only to partial ionization.

Complete answer:
For strong electrolytes, such as salts, strong acids and strong bases, the molar conductivity depends only weakly on concentration. On dilution there is a regular increase in the molar conductivity of strong electrolyte, due to the decrease in solute–solute interaction. Molar conductivity measures the efficiency with which a given electrolyte conducts electricity in solution. With the increase of degree of dissociation, the molar conductivity of both weak and strong electrolytes increases.
α=(λm)(λm)c=λλo\alpha = \dfrac{{({\lambda _m})\infty }}{{({\lambda _m})c}} = \dfrac{{{\lambda _{}}}}{{{\lambda _o}}}
Molar conductivity can be expressed in the following term given below:
Λm  = KC{\Lambda _m}\; = {\text{ }}\dfrac{K}{C}
Where KK is the specific conductivity and CCis the concentration in mole per litre.
In general, the molar conductivity of an electrolytic solution is the conductance of the volume of the solution containing a unit mole of electrolyte that is placed between two electrodes of unit area cross-section or at a distance of one-centimeter apart.
The unit of molar conductivity isSm2mol1S \cdot {m^2} \cdot mo{l^{ - 1}}.

Note:
We need to know that the degree of association is classified as the fraction of the total number of molecules that are connected or combined, resulting in a larger molecule being created. The degree of dissociation is the phenomenon of producing free ions carrying current, which at a given concentration is dissociated from the fraction of solute.