Redox Reactions And Electrochemistry Ques 334
Question: The standard potential at 298 K for the following half reactions are given against each:
$ Z{n^{2+}}(aq)+2{e^{-}}\rightarrow Zn(s) $ $ -,0.762V $ $ 2{H^{+}}(aq)+2{e^{-}}\rightarrow H_2(g) $ 0.000 V $ C{r^{3+}}(aq)+3{e^{-}}\rightarrow Cr(s) $ $ -,0.740V $ $ F{e^{3+}}(aq)+2{e^{-}}\rightarrow F{e^{2+}}(aq) $ 0.770 V Which is the strongest reducing agent-
Options:
A) Zn(s)
B) Cr(s)
C) $ H_2( g ) $
D) $ F{e^{2+}}( aq ) $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] The more negative the standard potential, the least the reduction tendency of the ion. The corresponding atom has largest oxidation tendency and thus is a strong reducing agent. In the present case. Zn is the strongest reducing agent.