Question

Is 13.0 mv at 25 °c. calculate the concentration of the zn2 (aq) ion at the cathode?

Answer 1

To determine the pH of the solution in the second compartment of a galvanic cell, use the Nernst equation to find the value of Q and then calculate the pH using the relationship between pH and concentration of H+ ions.

Step-by-step explanation:

The question seems to be related to a galvanic cell where zinc (Zn) is the anode and copper (Cu) is the cathode. The measured potential in the cell is given as 0.26 V at 25°C. To determine the pH of the solution in the second compartment, we need to use the Nernst equation. The Nernst equation is given by :Ecell = Eº - (0.0592/n) × log(Q)

Since the measured potential and standard potential (Eº) for the cell are given, we can use the equation to find the value of Q and then calculate the pH of the solution using the relationship between pH and concentration of H+ ions.

Answer 2

Answer:
Zn =⇒ Zn+2(0.10) + 2e- (anode)
Zn+2(?M) + 2e- === Zn(s) (cathode)

Zn + Zn+2(?M) ===⇒ Zn+2(0.10) + Zn
E = E^o -0.0592 log Q; in this case E^o is zero.
E = - 0.0592 /n logQ where n is the number of electrons transferred, in this
case n = 2
23 mV x 1 volt/1000mv = 0.023 Volts
0.023 = -0.0592 / 2 log(0.10) / [Zn+2]
0.023 = -0.0296 { log 0.10 – log [Zn+2] }
0.023 = -0.0296{ -1 - log[Zn+2] }
0.023 = +0.0296 + 0.0296log[Zn+2]
-0.0066 = 0.0296log[Zn+2]
-0.22= log[Zn+2]
[Zn+2] = 10^-0.22 = 0.603 Molar