![]() Next we draw a double vertical line, and this represents our salt bridge. So we've represented, let me use red for this, we've represented our Zinc electrode and we've represented our Zinc 2+ ions. Your aqueous solution of Zinc 2+ ions, so we're gonna write our Next you draw a single vertical line which represents a phase boundary between solid Zinc and So our anode here, our anode is Zinc, so we have solid Zinc, let And so let's go ahead and start writing our shorthand notation. So it's a little bit annoying to draw out a picture like this every time you want to represent a Voltaic Cell, so there's a shorthand notation that's used so you don't have to keep drawing things out. Alright, now finally let's think about shorthand notation. So it's easy to remember what's happening in the salt bridge. And cations migrate to the cathode, so we have sodium cations here, and cations migrate to the cathode. So anions migrate to the anode, that's easy to remember that. Alright, let's also think about the salt bridge really quickly, alright? So we have, let me goĪhead and use red here, we have sulfate, we have sulfate anions in our salt bridge, and anions migrate to the anode. And a good way to remember this is an ox and red cat, right? So, an ox, oxidation occurs at the anode, and then red cat, let me write that one down over here, so red cat, reduction Occurs at the cathode, so this must be the cathode. Occurs at the anode, so this must be our anode. Let's go back to our half-reactions and think about the electrodes. So that's our spontaneous redox reaction that's creating an electric current because of the flow of the electrons in the wire here. More Copper deposited on our Copper electrode, so think about more Copper, more Copper deposited on the surface of our Copper electrode. Think about what happens, we're losing Zinc, so let me use a different color here, so we're gonna lose Zinc over time and we're going to gain Copper, right? So we're going to get So this gives us, Zinc 2+ ions in solution and also solid Copper. And for the products, over here we would have Zinc 2+ ions and solid Copper. We will have solid Zinc and we will have Copper 2+ ions, so we write that in here. So we add these together, and we know that the two electrons that were lost by Zinc are the same electrons thatĪre gained by Copper 2+, we can cancel those out, and so for our reactants If we add together our two half-reactions we get our overall redox reaction. So "Leo the Lion Goes Ger", is a good way to remember So remember, loss ofĮlectrons is oxidation, and gain of electrons is reduction. So this would be solid Copper, and since we gained electrons this is our reduction half-reaction, so this represents a So think about what happens if you add two electrons to a Copper 2+ ion, you get solid Copper, right? So overall zero charge. And when those Copper 2+ ions come in contact with those electrons we get a reduction half-reaction. In solutions, this is an aqueous solution of Copper sulfate, so we have Copper 2+ ions in solution. ![]() So now we have these two electrons on our Copper electrode. So we have a wire set up and those two electrons are going to move, which is our electric current, right? So we get an electric current in our wire, and those two electrons move over to the electrode on the ![]() Those two electrons that we lost, these two electrons right here, are going to travel along our wire. So we've lost electrons, remember, when you lose electrons it's an oxidation reaction, or you could also lookĪt the oxidation states. This is our oxidation half-reaction, so this is an oxidation. So this is the losing two electrons, so we put the electrons So we have solid Zinc losing two electrons to turn into Zinc 2+ ions in solution. The atom will have to lose two electrons, so two electrons are leftīehind on the Zinc electrode. And so, we already know what happens on this electrode on the left, the Zinc electrode or the solid Zinc turns into Zinc 2+ ions. Remember, a Voltaic Cell uses a spontaneous redox reaction to create an electric current. ![]() Get into shorthand notation let's review the structure of the Galvanic or Voltaic Cell.
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