【Daily Question】Theoretical Foundation 2020.09.01
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This post was last edited by Qingse Nianhua on 2020-9-1 08:25. Multiple-choice question: Given that φθCu2+/Cu = +0.3419 V, φθFe3+/Fe2+ = +0.771 V, φθSn4+/Sn2+, and φθI2/I- = +0.5355 V, what is the order of reducing strength of their reduced forms from strongest to weakest? () A. Cu > I- > Fe2+ > Sn2+ B. I- > Fe2+ > Sn2+ > Cu C. Sn2+ > Cu > I- > Fe2+ D. Fe2+ > Sn2+ > I- > Cu Answer: C Hint: Extra rewards will be given to those who can explain the solution process; the answer can be seen in the response
This post was last edited by h20090630 on 2020-9-2 at 12:03. The smaller the value of C φθ, the stronger the reducing power of its reduced form. The order of electrode potentials is φθ(Sn4+ / Sn2+) < φθ(Cu2+ / Cu) < φθ(I2 / I-) < φθ(Fe3+ / Fe2-); therefore, the order of reducing strength is Sn2+ > Cu > I- > Fe2+.