Consider the reaction $$\begin{array} { l } M \stackrel { k _ { 1 } } { \longrightarrow } M _ { a ds } ^ { + } + e ^ { - } \ M + M _ { a d s } ^ { + } \stackrel { k _ { 2 } } { \longrightarrow } M _ { a d s } ^ { + } + M _ { s o l } ^ { + } + e ^ { - } \ M _ { a d s } ^ { + } \stackrel { k _ { s } } { \longrightarrow } M _ { s o l } ^ { + } \end{array}$$ -In the same mechanism, the charge transfer resistance (R_t) is given by A) $$\left( R _ { t } \right) ^ { - 1 } = F \left\{ b _ { 1 } k _ { 1 dc } \left( 1 - \theta _ { ss } \right) - b _ { 2 } k _ { 2 dc } \left( 1 - \theta _ { s s } \right) \theta _ { s s } \right\}$$ B) $$\left( R _ { t } \right) ^ { - 1 } = F \left\{ b _ { 1 } k _ { 1 dc} \left( 1 - \theta _ { ss } \right) + b _ { 2 } k _ { 2dc } \left( 1 - \theta _ { s s } \right) \theta _ { s s } \right\}$$ C) $$\left( R _ { t } \right) ^ { - 1 } = F \left\{ b _ { 1 } k _ { 1 d c } \left( 1 - \theta _ { s s } \right) + b _ { 2 } k _ { 2 dc } \theta _ { s s } \right\}$$ D) $$\left( R _ { t } \right) ^ { - 1 } = F \left( b _ { 1 } k _ { 1 d c } \left( 1 - \theta _ { s s } \right) - b _ { 2 } k _ { 2 dc } \theta _ { s s } \right\}$$

Question

Quizplus · Accepted Answer

The correct expression for the inverse of the charge transfer resistance in this mechanism includes both the first and second reactions contributing positively to the overall process. The first term, $b_{1}k_{1dc}(1-\theta_{ss})$, represents the contribution from the direct metal dissolution, which decreases as the surface coverage ($\theta_{ss}$) increases. The second term, $b_{2}k_{2dc}(1-\theta_{ss})\theta_{ss}$, accounts for the contribution from the reaction involving both the metal and its adsorbed ion, which is dependent on both the presence and absence of surface coverage. This combination reflects the overall dynamics of the electrochemical reaction on the surface, where both processes contribute to the charge transfer in a complementary manner.

Consider the Reaction -In the Same Mechanism, the Charge Transfer Resistance (Rt) Is

Consider the Reaction -In the Same Mechanism, the Charge Transfer Resistance (R_t) Is