eguruchela

Electrochemistry


Ohm's Law

$$ v = IR $$ $$ R = \rho \frac{l}{a} $$ $$ \text {Where V is Potential difference,} $$ $$ \text {R is Resistance,} $$ $$ \text {I is current,} $$ $$ \text {ρ is specific resistance,} $$ $$ \text {l is lenght of conductor and } $$ $$ \text {a is the cross-section of conductor.} $$

Conductance

$$ G = \frac{1}{R} $$ $$ \text {The specific conductance k =} \frac{1}{\rho} $$ $$ \text { Cell constant } \rho = \frac{l}{a} $$ $$ k = G. \sigma $$

Molar conductance

$$ \text {Molar conductance }A_{\,M} ( \Phi _{\,C}) = \frac{\text {1000 x k}}{\text{ C (or M)}} $$ $$ \text {where C is concentration of electrolyte in terms of molarity.} $$

Equivelant conductance

$$ \text {Equivelant conductance }A_{\,M} (A _{\,C}) = \frac{\text {1000 x k}}{\text{ C (or N)}} $$ $$ \text {where C is concentration(normality)} $$ $$ A_M = A_{N} \text { x}(n-factor) $$ $$ A _{\,o} = \lim_{C \to 0} A _{\,C} $$ $$ \text {where} A _{\,o} = \text {equivalent conductance at infinite dilution.} $$

Faraday's first law of electrolysis

$$ m = Zit $$ $$ \text {where m is mass of substance deposited, } $$ $$ \text {Z is electrochemical equivalent,} $$ $$ \text {i is current and} $$ $$ \text {t is time.} $$ $$ Z = \frac {\text{Atomic mass}}{\text{n x F}} $$ $$ \text {Faraday's second law of electrolysis} $$ $$ \frac {m _{\,1}} {m _{\,1}} = \frac {E _{\,1}} {E _{\,1}} $$ $$ \text {where E is equivalent weight.} $$