Electrochemistry - Result Question 76
####24. The standard reduction potentials at $298 K$ for the following half cells are given :
$$ \begin{aligned} Zn^{2+}(a q)+2 e^{-} \rightleftharpoons Zn(s) ; E^{\circ}=-0.762 V \ Cr^{3+}(a q)+3 e^{-} \rightleftharpoons Cr(s) ; E^{\circ}=-0.740 V \end{aligned} $$
$$ \begin{aligned} 2 H^{+}(a q)+2 e^{-} & \rightleftharpoons H _2(g) ; E^{\circ}=0.000 V \ Fe^{3+}(a q)+e^{-} & \rightleftharpoons Fe^{2+}(a q) ; E^{\circ}=0.770 V \end{aligned} $$
Which is the strongest reducing agent?
(1981, 1M)
(a) $\operatorname{Zn}(s)$
(b) $\operatorname{Cr}(s)$
(c) $H _2(g)$
(d) $Fe^{2+}(a q)$
Objective Questions II
(One or more than one correct option)
Show Answer
Answer:
Correct Answer: 24. $(a, b, d)$
Solution:
- Lower the value of $E^{\circ}$, stronger the reducing agent.
