The emf of Cd|Cd2+ (? M) || Ni2+ (1.0 M) | Ni is 0.24 V. What is the concentration of Cd2+?
Lets find Eo 1st
from data table:
Eo(Cd2+/Cd(s)) = -0.4 V
Eo(Ni2+/Ni(s)) = -0.25 V
As per given reaction/cell notation,
cathode is (Ni2+/Ni(s))
anode is (Cd2+/Cd(s))
Eocell = Eocathode - Eoanode
= (-0.25) - (-0.4)
= 0.15 V
Number of electron being transferred in balanced reaction is 2
So, n = 2
we have below equation to be used:
E = Eo - (0.0592/n) log {[Cd2+]^1/[Ni2+]^1}
0.24 = 0.15 - (0.0592/2) log ([Cd2+]^1/1.0^1)
log ([Cd2+]^1/1.0^1) = -3.041
([Cd2+]^1/1.0^1) = 9.109*10^-4
[Cd2+] = 9.11*10^-4 M
Answer: 9.11*10^-4 M
Get Answers For Free
Most questions answered within 1 hours.