Question

(1) What is specific conductivity? What is its relation with specific resistance? What is its unit?
(2) What is Ohm’s law?

Answer 1

Hint: The conductivity of material is the property of material due to which the material allows the flow of ions through itself and thus conduct electricity. In general, it is defined as the reciprocal of resistance of that material. SI unit of conductance is S (siemens).
Resistance is the property of material to oppose the flow of electric current passing through it.

Complete Step-by-Step Solution:
(1) Specific conductivity: The reciprocal of resistivity is called specific conductivity. It is defined as the conductance between the opposite faces of one-centimeter cube of conductor. It is denoted by k (kappa). Specific conductivity is the measure of the ability of that material to conduct electricity.

Specific resistance is defined as the resistance offered by unit length and unit cross section of the substance to a current when a voltage is applied to it.
Its SI unit is Ω-m.

$k = \dfrac{1}{\rho }$
The unit of specific conductivity is:
$k = \dfrac{1}{{ohmcm}}$

     =$ohm^- 1\,cm^- 1$

The specific conductivity of a solution at a given dilution is the conductance of one cm cube of the solution. It is represented by k (kappa).
Thus, the relationship between specific conductivity and specific resistivity is that specific conductivity is the reciprocal of specific resistivity.

(2) Ohm’s Law: Ohm’s law states that the strength of current flowing through a conductor is directly proportional to the potential difference applied across the conductor and inversely proportional to resistance of the conductor.
$V \propto I$
$V = RI$
$R = \dfrac{V}{I}$
R is a constant R = resistance.

Note: The specific conductivity of a solution of electrolyte depends upon the dilution or molar concentration of the solution.
Ohm’s law is an empirical relation which accurately describes the conductivity of the vast majority of electrically conductive material over many orders of magnitude of current.