I'm trying to perform a potentiometric titration as part of my high school laboratory work, by reducing iron(III) to iron(II), and measuring the voltage change as I add cobalt(II) (to reduce it).

The methods that I have found online all point to using an $\ce{Ag/AgCl}$ or calomel reference electrode and an inert sensing electrode. When I look at the diagram, both the sensing and reference electrode are immersed in the solution of iron(III). Currently, these electrodes are too expensive and my school does not have access to it.

Can I just fill a separate beaker with $\ce{KCl}$ and put my $\ce{Ag/AgCl}$ wire into it, and connect the 2 solutions using a salt bridge? Or do I need to submerge both electrodes in the same solution?

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    $\begingroup$ Do you have a Pt wire to be used as inert? $\endgroup$ – Alchimista Feb 25 '19 at 11:44
  • $\begingroup$ Hi, yes I do have that as the inert electrode $\endgroup$ – malhi3 Feb 28 '19 at 7:34
  • $\begingroup$ Then you can try to use them at least for demonstration plunging directly both. I am used to quasi-reference electrode just in non aqueous media. Give it a try and look for its stability. Using a separate beaker would be the same and you won't have the electrode at the right place. But you can use also the bridge so to have chloride around it. I would look at both setup then choose what gives you the better curve. Simply, at first, look for the stability of whatever potential reading, without titration. $\endgroup$ – Alchimista Feb 28 '19 at 8:18