### Calculating K for reaction using half reactions

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**Sat Feb 11, 2017 5:32 pm**In the textbook example 14.8 on page 586, the question asks to calculate the equilibrium constant at 25 degrees C for AgCl(s)--->Ag+(aq)+Cl-(aq). The two half reactions that are required to use are

R: AgCl(s) + e- ---->Ag(s) +Cl-(aq) E=+0.22V

L: Ag+(aq) +e- -----Ag(s) E=+0.80V

It says that the second equation is reversed. Therefore, wouldn't it make that equation the anode? I thought that the more positive E value was the cathode? Could someone please explain how to know which equation to reverse and how the value of E ties into that?

Thank you!

R: AgCl(s) + e- ---->Ag(s) +Cl-(aq) E=+0.22V

L: Ag+(aq) +e- -----Ag(s) E=+0.80V

It says that the second equation is reversed. Therefore, wouldn't it make that equation the anode? I thought that the more positive E value was the cathode? Could someone please explain how to know which equation to reverse and how the value of E ties into that?

Thank you!