Question 14.25

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Gavin Kellerman 1D
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Joined: Sat Jul 09, 2016 3:00 am

Question 14.25

Postby Gavin Kellerman 1D » Mon Feb 19, 2018 3:10 pm

I'm a bit confused about why a more negative standard reduction potential makes a metal a better reducing agent. I thought that negative cell reduction potentials make a redox reaction non-spontaneous, so you would want your cathode to be more positive.

Anna Goldberg 2I
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Re: Question 14.25

Postby Anna Goldberg 2I » Mon Feb 19, 2018 3:28 pm

Metals that are reducing agents are in the anode, as they themselves are becoming oxidized, which occurs in the anode. Thus, you want these metals to have a more negative standard reducing potential, as this will make the Ecell more positive, from the relationship: Ecell=Ecathode-Eanode (you want to have a more negative Eanode in order to have a more positive Ecell-thus stronger reducing agents have a more negative standard reducing potential).

Anna Goldberg 2I
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Joined: Fri Sep 29, 2017 7:04 am
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Re: Question 14.25

Postby Anna Goldberg 2I » Mon Feb 19, 2018 3:29 pm

As well, a more positive Ecell makes G more negative, and thus the reaction more spontaneous (from G=-nFE).

Tasnia Haider 1E
Posts: 55
Joined: Sat Jul 22, 2017 3:01 am

Re: Question 14.25

Postby Tasnia Haider 1E » Tue Feb 20, 2018 4:48 pm

In this question, Zinc has a more negative standard potential than Chromium, but the answer key shows that chromium is the stronger reducing agent. Why is that?


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