6N.15

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Lizette Noriega 1H
Posts: 105
Joined: Wed Sep 18, 2019 12:15 am

6N.15

Postby Lizette Noriega 1H » Tue Mar 03, 2020 5:39 pm

I have a question about the following problem: Calculate the potential of a cell constructed with two nickel electrodes. The electrolyte in one compartment is 1.0 M Ni(NO3)2(aq). In the other compartment, NaOH has been added to a Ni(NO3)2 solution until the pH 5 11.0 at 298 K. See Table 6I.1.

How do you know which half-reactions to use? We end up using Ni (2+) + 2e --> Ni but what happens to the NO3? Is it involved in the salt bridge?

Thanks!

Chem_Mod
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Re: 6N.15

Postby Chem_Mod » Thu Mar 05, 2020 12:22 pm

NO3- and Na+ are more spectator ions in the sense that they are not relevant here. The NO3- is not important because it is the Ni2+ ion that undergoes a redox reaction to form Ni(s) ie the electrode. You can't really add Ni2+ ions on its own, so you add Ni(NO3)2 to be a source of Ni ions. Similarly, NaOH is a source of OH- ions because you can't add OH- on its own.

005384106
Posts: 101
Joined: Sat Aug 24, 2019 12:16 am

Re: 6N.15

Postby 005384106 » Wed Mar 11, 2020 5:42 pm

What role do the spectator ions play in this reaction?


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