Question

Explain the variation of molar conductivity with concentration for strong electrolyte and weak electrolyte with the help of diagram.

Calculate the degree of dissociation (α) of CH₃COOH if Λₘ and Λ°ₘ of CH₃COOH are 48 S cm² mol⁻¹ and 400 S cm² mol⁻¹ respectively.

The resistance and conductivity of a conductivity cell containing 0·001 M KCl solution at 298 K are 1200 Ω and 1·5 × 10⁻⁴ S cm⁻¹. Calculate its cell constant and molar conductivity.

Read the passage given below and answer the questions that follow : Oxidation-reduction reactions are commonly known as redox reactions. They involve transfer of electrons from one species to another. In a spontaneous reaction, energy is released which can be used to do useful work. The reaction is split into two half reactions. Two different containers are used and a wire is used to drive the electrons from one side to the other and a Voltaic/Galvanic cell is created. It is an electrochemical cell that uses spontaneous redox reactions to generate electricity. A salt bridge also connects to the half cells. The reading of the voltmeter gives the cell voltage or cell potential or electromotive force. If E°cell is positive the reaction is spontaneous and if it is negative the reaction is non-spontaneous and is referred to as electrolytic cell. Electrolysis refers to the decomposition of a substance by an electric current. One mole of electric charge when passed through a cell will discharge half a mole of a divalent metal ion such as Cu²⁺. This was first formulated by Faraday in the form of laws of electrolysis. The conductance of material is the property of materials due to which a material allows the flow of ions through itself and thus conducts electricity. Conductivity is represented by k and it depends upon nature and concentration of electrolyte, temperature etc. A more common term molar conductivity of a solution at a given concentration is conductance of the volume of solution containing one mole of electrolyte kept between two electrodes with the unit area of cross-section and distance of unit length. Limiting molar conductivity of weak electrolytes cannot be obtained graphically.