What Is Molar conductivity?

Do you think that the conductivity of a solution would vary when you alter the concentration? Have you never tried an experiment like that? It is an absolutely important concept and cava deeper into the depths of this concept of conductivity variation.

Friedrich Wilhelm Georg Kohlrausch in 1875-79 established that to high accuracy in dilute solutions, molar conductivity is composed of individual contributions of ions. This is known as Kohlrausch’s law of independent ionic migration. 

Friedrich Kohlraush studied the molar conductivity of different electrolytes at different concentrations. He observed an increase in the molar conductance of an electrolytic solution with the increase in the dilution.

What is the molar conductivity?

Molar conductivity is the property of conductance of a solution containing an electrolyte mole or is a function of the ionic resistance of a solution or concentration of salt. Therefore, it is not a constant.

In simple words, molar conductivity can also be defined as the conductive power of all ions formed by dissolving an electrolyte mole in a solution. Molar conductivity is the property of an electrolytic solution that is mainly used to determine the efficiency of an electrolyte given in the conduction of electricity in a solution. Therefore, it is not a constant.

Molar Conductivity Formula

The expression which is given below is used to represent molar conductivity mathematically.

Λm = k / c

Where K is specific conductivity and C is concentration in moles per litre.

In general, the molar conductivity of the electrolyte solution is a conductance of the solution volume containing the electrolyte mole unit which is placed between two unit-sectional electrodes or at a distance of one centimetre.

The molar conductivity unit is S⋅m²⋅mol-¹.

Variation of molar conductivity with concentration

Molar conductivity of weak and strong electrolytes increases with a decrease in concentration or dilution. We know that molar conductivity is the conductivity offered by a one-mole ion. Even after dilution, we still consider the same mol ion unit. However, increased dilution produces more dissociation of electrolytes into ions and effectively increases the number of active ions in the solution. This active ion provides more conductivity.

For weak electrolytes, however, molar conductivity of lower concentration. In contrast, electrolytes have lower molar conductivity at higher concentrations because the dissociation levels are reduced

 For strong electrolytes, increased concentration results in a sharp increase in conductivity.

In terms of specific conductivity, it can be seen that conductivity increases when electrolyte concentration increases. Specific conductivity totally depends on the number of ions in the solution volume unit. On dilution, dissociation increases, causing ions that bring today to increase in solution. But because of dilution, the number of ions in the unit volume decreases in the solution. This causes conductivity reduction.

Electrolytic Conduction

Electrolytes pass electricity because of the free ions contained in them. This is similar to the case of a metallic conductor, where electrons are free to support electrical conduction. Electrolyte conduction is explained based on the equation or Arrhenius theory.

We know that electrolyte solutions are made from certain salt dissolution. Salt does not need to be ionic. The only criterion is that the compound must consist of oppositely-charged ions.

Arrhenius’s theory explains that when neutral electrolytes are dissolved in water, electrolyte molecules are divided into two ions that are charged differently. Which is required positively called a cation and a negatively charged called anion. The theory assumes that ions are already in electrolytes but bound together with electrostatic forces and, therefore, are neutral. But once dissolved, the ion is dissociated from the form of bound.

Specific Conductivity 

The extent to which the sample electrolytic solution provided can do an electric current called the conductant. Conversely, the extent to which the sample provided from the electrolytic solution can withstand the flow of electric current is called resistance. Of course, conductance is a resistance of a particular electrolytic solution. The conductance unit is S (Siemens).

Specific conductivity or conductivity is the size of the ability of electrolytic solutions to do electricity. The specific conductivity unit is Siemens per metre, better represented as S / M

Conclusion:

We learned all about molar conductivity, its history, definition, formula, variation, electrolytic conduction, and specific conductivity. All the stages of molar conductivity are prepared easier so that every student can learn all the things easily without facing any problems. And lastly, the above article helped you a lot but you enjoyed the article but if you still have queries regarding this topic you can ask below. Our team will contact you as soon as possible to resolve your queries. You can also share your experience with this article in the comment section.