Question

Enter electrons as e Use smallest possible integer coefficients. If a box is not needed, leave it blank. A voltaic cell is constructed from a standard Mn2+ Mn half cell (Ered=-1.180V) and a standard Zn²+ Zn half cell (Eºred =-0.763V). The anode reaction is: The cathode reaction is: The spontaneous cell reaction is: The cell voltage is Data.Cot: Show all

Answer 1

We know that, the significance of electrode is element having more positive value of reduction potential has more tendency to undergo reduction & hence it acts as a cathode.

If we compare electrode potentials of Mn & Zn , it is clear that Zn will act as anode.

The anode reaction is , Mn (s) $\rightarrow$ Mn ²⁺ (aq) + 2 e ^-

The cathode reaction is,  Zn ²⁺ (aq) + 2 e ^-$\rightarrow$ Zn (s)

The standard cell potential of cell is E ⁰ cell = E ⁰ reduction potential of cathode - E ⁰ red. potential of anode.

$\therefore$ E ⁰ cell = ( E ⁰_{Zn ²⁺ I Zn} ) - ( E ⁰_{Mn ²⁺ I Mn} )

$\therefore$ E ⁰ cell = - 0.763 V - ( - 1.180 V )

$\therefore$ E ⁰ cell = 0.417 V