Explain the difference between an electrochemical cell and electrolytic cell. State Kohlrausch's law and write its applications.
Step 1: Difference Between Electrochemical and Electrolytic Cells: Feature & Electrochemical Cell & Electrolytic Cell
Energy Conversion & Chemical to electrical & Electrical to chemical
Spontaneity & Spontaneous reaction & Non-spontaneous reaction
Example & Galvanic/Daniel cell & Electrolysis of NaCl
Step 2: Kohlrausch's Law: \[ \Lambda_m^0 = \lambda^0_+ + \lambda^0_- \] where \( \lambda^0_+ \) and \( \lambda^0_- \) are the limiting molar conductivities of cations and anions, respectively.
Step 3: Applications: - Used to calculate the molar conductivity of weak electrolytes. - Helps in determining dissociation constants of weak acids and bases.
Standard electrode potential for \( \text{Sn}^{4+}/\text{Sn}^{2+} \) couple is +0.15 V and that for the \( \text{Cr}^{3+}/\text{Cr} \) couple is -0.74 V. The two couples in their standard states are connected to make a cell. The cell potential will be:
To calculate the cell potential (\( E^\circ_{\text{cell}} \)), we use the standard electrode potentials of the given redox couples.
Given data:
\( E^\circ_{\text{Sn}^{4+}/\text{Sn}^{2+}} = +0.15V \)
\( E^\circ_{\text{Cr}^{3+}/\text{Cr}} = -0.74V \)
(a.)Write the anode and cathode reactions and the overall cell reaction occurring in a lead storage battery during its use.