Redox Reactions And Electrochemistry Ques 87
Question: The standard reduction potential $ NaCl $ for the half reactions are as $ Zn=Z{n^{2+}}+2{e^{-}};E^{o}=+0.76,V $ $ Fe=F{e^{2+}}+2{e^{-}};E^{o}=+0.41,V $ The EMF for cell reaction $ F{e^{2+}}+Zn,\to ,Z{n^{2+}}+Fe $ is [IIT 1988; CBSE PMT 1993, 96; BHU 1995, 2000; CPMT 2000; KCET 2000; AIIMS 2001; Orissa JEE 2002]
Options:
A) $ -,0.35,V $
B) $ +,0.35,V $
C) $ +,1.17,V $
D) $ -,1.17,V $
Show Answer
Answer:
Correct Answer: B
Solution:
In this reaction $ F{e^{2+}}+\overset{0}{\mathop{Zn}},\to \overset{2+}{\mathop{Zn}},+\overset{0}{\mathop{Fe}}, $ $ EMF={E_{cathode}}-{E_{anode}} $ $ =-0.41-(-0.76) $ $ EMF=+0.35 $ V.