14.37 C

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Michelle Lu 1F
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Joined: Thu Jul 27, 2017 3:01 am
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14.37 C

Postby Michelle Lu 1F » Tue Feb 20, 2018 11:53 pm

Why is the 2H+ + 2e- => H2 the reduction reaction? The standard reduction potential for that reaction is 0, whereas the the standard reduction potential for the other reaction 2Cl- => Cl2 + 2e- is +1.36, which is greater and therefore has stronger oxidizing power and should be the reduction reaction?

Justin Lau 1D
Posts: 51
Joined: Sat Jul 22, 2017 3:00 am

Re: 14.37 C

Postby Justin Lau 1D » Wed Feb 21, 2018 10:25 am

Basically, the question has an unfavorable cell diagram. The answer is a negative voltage, which tells you that the Cl2 "anode" is actually the cathode; that is, the electrons would flow from right to left in this cell.

Lauren Seidl 1D
Posts: 51
Joined: Fri Sep 29, 2017 7:06 am

Re: 14.37 C

Postby Lauren Seidl 1D » Wed Feb 21, 2018 12:40 pm

Because anode is always written on the left side of the cell diagram, you still have to calculate the Ecell = Ecathode - Eanode, which does give you a negative voltage. This tells you that the reaction is not spontaneous, and that the electrons would flow in the opposite direction.

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