Redox Reactions And Electrochemistry Ques 709
Question: Given the following half reactions:
$ {A^{2+}}+{e^{-}}\to {A^{+}},E^{o}=+1.70V $ $ {B^{2+}}+2{e^{-}}\to {B^{+}},E^{o}=+0.60V $ $ {C^{3+}}+{e^{-}}\to {C^{2+}},E^{o}=+0.90V $ The only reaction that could be used in titration would be
Options:
A) $ {A^{+}} $ with $ {B^{4+}} $
B) $ {A^{+}} $ with $ {C^{3+}} $
C) $ {A^{2+}} $ with $ {C^{2+}} $
D) $ {C^{2+}} $ with $ {B^{4+}} $
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ \begin{aligned} & ,A^{2}+{e^{-}}\to {A^{+}},E=1.7V \\ & {C^{2+}}\to {C^{3+}}+{e^{-}},{E^{\circ }}=-0.9V \\ & {A^{2+}}+{C^{2+}}\to {A^{+}}+{C^{3+}},{E^{\circ }}=0.8V>0, \\ \end{aligned} $ spontaneous.
