Homework SourseA voltaic cell is constructed with two halfcells The first i
A voltaic cell is constructed with two half-cells: The first is the standard Zn2+(aq)|Zn(s) half-cell in which [Zn2+] = 1.00 M. The second is a nonstandard hydrogen electrode in which the pressure of H2 = 1.00 atm. The hydrogen electrode is immersed in an unknown solution. The observed cell voltage is 0.638 V at 25.0 oC. Calculate the pH of the solution.
Solution
Cell is Zn/Zn2+ || 2H+ /H2
E = -E(Zn2+-Zn) -0.059/2 log(Zn2+/[H+]^2)
0.638= -(-0.76) -(0.0295)log(1/[H+]^2)
[H+] = 0.00855,
pH = -log( 0.00855) = 2.068
![A voltaic cell is constructed with two half-cells: The first is the standard Zn2+(aq)|Zn(s) half-cell in which [Zn2+] = 1.00 M. The second is a nonstandard hydr](/WebImages/33/a-voltaic-cell-is-constructed-with-two-halfcells-the-first-i-1095090-1761577315-0.webp "A voltaic cell is constructed with two half-cells: The first is the standard Zn2+(aq)|Zn(s) half-cell in which [Zn2+] = 1.00 M. The second is a nonstandard hydr")
