Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: NYM on April 05, 2008, 01:14:10 PM

An electrochemical cell consists of a Zn electrode in 0.200 M Zn^{2+} (aq) and a Ag electrode in 0.100 M Ag^{+} (aq).
KCl (s) is added to the Ag electrode. E is measured to 1.04 V and E^{o} is 1.56 V. Determine [Ag^{+}].
Nernst equation:
E = E^{o}  0.059 V/2 * log ([Zn^{2+}]/[Ag^{+}]) =>
1.04 V = 1.56 V  0.059V/2 * log (0.200/[Ag^{+}]^{2} =>
[Ag^{+}] = 6.87*10^{10} M.
The right answer is 7.36*10^{10} M. What am I doing wrong here?

Nernst equation:
E = E^{o}  0.059 V/2 * log ([Zn^{2+}]/[Ag^{+}]) =>
1.04 V = 1.56 V  0.059V/2 * log (0.200/[Ag^{+}]^{2} =>
[Ag^{+}] = 6.87*10^{10} M.
The right answer is 7.36*10^{10} M. What am I doing wrong here?
recalculate using 0.0592

Nernst equation:
E = E^{o}  0.059 V/2 * log ([Zn^{2+}]/[Ag^{+}]) =>
1.04 V = 1.56 V  0.059V/2 * log (0.200/[Ag^{+}]^{2} =>
[Ag^{+}] = 6.87*10^{10} M.
The right answer is 7.36*10^{10} M. What am I doing wrong here?
recalculate using 0.0592
D'oh! Thank you for pointing that out :D