Unit of Molar Conductivity: Overview, Questions, Preparation

Molar conductivity is not a constant. It is defined as one mole containing a conductance property of the electrolyte. It is a function to determine the ionic strength of the mixture or if it contains any salt. In simple words, it is used to determine the ionic power of the solution dissolved in the electrolyte.

The formula of molar conduction shows the relation between specific conductivity and the concentration of the mole, and it can be written as:

Λ_m = K / C

Here, specific conductivity is denoted as K,

The concentration of mole per liter is denoted as C

In other words, we can say that it is used to determine the conductance of electrolytic solution and the quantity of mole placed between the two units of electrodes at the distance of 1 centimeter.

The unit of molar conductivity is S. m². Mol^-1.

Specific Conductivity

Specific conductance is the sample of the electrolytic solution on which electric current is measured. On the contrary, the sample of electrolytic solution that can resist the electric current flow is known as resistance. The conductance is inversely proportional to the resistance of the electrolytic solution.

S (Siemens) is the SI unit of conductance denoted as S/m.

G = 1 / R

R = p I / A

G = 1 / p x A / I

G = k A / I

Here, the specific resistivity is denoted as P,

Specific conductivity is denoted as K;

It is also known as reciprocal of resistivity (ρ). Both are inversely proportional to each other.

K 1 / p = C / R

There are some factors on which specific conductivity depends. These factors are listed below:

1. Temperature
2. The size of the electrolytic ions in the solution
3. The nature of the electrolytic solution
4. The concentration of the electrolytic solution
5. The viscosity and the nature of the solvent

Units of Molar Conductivity in Class 12

The chapter 'Atoms and Molecules' holds a weightage of 7 marks in total as per the new pattern of CBSE 2021. It includes 3 questions in total that consist of one objective type question of 1 mark and 2 short questions of 3 marks each.

Example 1) Write the unit of Molar conductivity.
Answer – The unit of molar conductivity is S. m². Mol^-1.

Example 2) State the formula of Specific Conductivity.

Answer –  The formula of Specific Conductivity is K 1 / p = C / R

Example 3) Write the SI unit of Conductance.

Answer – The Si unit of conductance is S (Siemens), it is represented as S/m.

Q: What do you mean by Molar conductivity?

Q: What is Specific Conductivity?

Q: What is Resistance?

Q: What are the factors of specific conductivity?

Q: What is limiting Molar conductivity?

Q: What are the K and C in molar conductivity called?