Galvanic Cell (Simplified) - Video Tutorials & Practice Problems

Galvanic Cell (Simplified) Concept 1

now a galvanic cell, also known as a voltaic cell is a spontaneous cell that produces or discharges electricity, therefore making it a battery. Now we're going to say that it uses stored chemical energy and converts it into electrical energy with our galvanic or will take So we have two types of electrodes we have are an ode and our cathode the animal itself represents are negatively charged metal electrode. And this is the compartment where oxidation occurs. So the anodes is oxidation. Remember with oxidation we have the loss of electrons. So here with oxidation we say we lose electrons. The cathode represents our positive metal electrode and it's a compartment where reduction occurs. And remember with reduction we say we gain electrons. So we're gaining electrons here. Now if we look here at this image of our galvanic cell, remember we said that our And out here is negative and our catholic here is positive. So here this represents our anodes are metal electrode and it looks like the electrode here is zinc and our capital which is positive is this metal electrode here, which is copper. Remember we said that the anodes loses electrons. So electrons are literally leaving this electrode and they're heading towards our cathode. So we have the flow of electrons going from a node two cathode. So here's our an out here and here is our calf out here now next we're gonna say we have a salt bridge. Now what's the whole point of a salt bridge, Well the whole point of a salt bridge. If you've taken physics, if you haven't taken physics, it's to help to close the circuit of our galvanic or or or takes up. So here we have negatively charged ions heading the opposite direction. So here the flow of light charges flowing opposite directions helps to close itself. And we're gonna say here that our salt bridge is just a tube that connects both half cells to one another and allows for the flow of neutral ions. Now you may say neutral ions, that sounds like a misnomer. How can an ion that possesses a charge be neutral? Well, when we say neutral ions, it just means the ions within the solution that possess no acidic or basic properties. When you're an ion you can be acidic, basic or neutral for this galvanic or voltaic cell to work properly. We need the ions to be neutral. They cannot be acidic or basic in nature. So if we take a look here within our salt bridge, which is this to pier, which connects the two together, we have our negative bromide ions heading the opposite direction of the electrons, the electrons are heading this way and the negative ions had to head this way. So here they're moving towards the annual compartment. sodium ions also represent neutral ions. They're heading towards the cathode compartment and we're going to say here that this movement of electrons from the an ode to the cathode is what's going to help generate electricity. And we read this by using a volt meter. So the volt meter is just a device that records the amount of electricity generated by the galvanic cell. So that's what we can say in terms of this image of our galvanic cell.

Galvanic Cell (Simplified) Example 1

the purpose of the galvanic cell is to a purify solids be allowed for only oxidation seen, generate electricity or d to consume electricity. Alright, so no. Where did we talk about purifying solid through the process of a galvanic or voltaic cell? So this would be out now. Galvanic cell utilizes a redox reaction, A spontaneous redox reaction in order to generate or create electricity. Remember, redox reactions involve both reduction and oxidation. It wouldn't only be oxidation and in defining and describing a galvanic slash voltaic cell, I said that they produce or create electricity. So they're generating electricity to say they're consuming electricity is the opposite. Remember a galvanic, which is the same thing as a voltaic cell. They're just batteries they're making or discharging electricity. Okay, so it's being used. Uh they're just using it. So they're a battery at the end of the day. So, the answer here will be options.

Galvanic Cell (Simplified) Example 2

now remember in our discussion of the galvanic cell, we talked about the two metal electrodes involved here, we had our anodes and cathodes. Remember in the anodes, we have the loss of electrons. If we take a look here at the zinc compartment, we know that it represented the anodes and we know what happened here was that zinc was oxidized to zinc to iron. More zinc. I'll So what does that entail? Well, we know that the zinc metal electrode is losing electrons over time and as it loses the electrons, it's going to produce zinc two plus ions. So here we see the electron traveling away from the metal zinc electrode And producing as a result a sink two plus iron. Now, what does this do over time? Well, you might hear from your professor that the anodes dissolves away. So the an ode dissolves away. Given enough time over time our zinc is going to become smaller and smaller, so portion of it of it will disappear. So pieces of it will go away because we're losing electrons. And over time that adds up to mass. What would the animal reaction look like? Well, here, if our zinc solid is losing electrons, the electrons loss would have to be products. It's producing two plus ions ions would be a quiz in solution. And here are the two electrons. It's lost. On the other side, the catholic is gaining electrons. So here the surface of the catheter is gaining electrons. So over time the surface becomes more negative because the surface is getting a slight negative charge, it's going to attract the positive copper two plus ions floating within the solution. So they're going to be attracted the electrons and traveled towards the surface and when they come into the contact with the electrons on the surface there neutralized, thereby becoming copper solid. So we're getting uh n crusting effect on top of the copper metal electrode of more copper. You may hear this, that cathode plate out and that's because of the partial negative charges gaining. You're gonna have these metal cat ions in the solution adhering to the surface, thereby making the electorate itself bigger and bulkier over time. Now, what does that look like in terms of a half reaction? Well, here we'd say the copper two plus ion is gaining electrons. So the electrons will be reacting. It gains those two electrons and thereby neutralizing itself to make copper solid. Now here we can give the overall reaction from this. Remember, your electrons are always canceling out and then you bring down everything else. So we have zinc solid plus copper. Two ion produces zinc. Two plus ion plus copper solid. This will represent our overall reaction. Now, if we look at this example from what we just covered, we can say how many electrons are transferred between the zinc and copper electrodes in the galvanic cell. What we can say here that two electrons and two electrons. So two electrons are being canceled from both half reactions. That's because two electrons are being transferred. So here, my answer would have to be option B. So remember the anodes where oxidation occurs, were losing electrons, and given enough time, the animal itself could start diminishing size. The capital over time gains electrons, giving itself a negative surface, which thereby attracts the metal cat ions already dissolved within the solution. This costs the capital over time to get a little bit bigger. All right, so just keep this in mind when looking at a typical galvanic cell with two metal electrodes.

Galvanic Cell (Simplified) Concept 2

And electrolytic cell is a non spontaneous cell that utilizes electrolysis in order to operate. Now, electrolysis is when we have chemical reactions that consume external cam electrical electrical energy in order to occur. Now we're going to stay here no matter the cell, whether it be an electrolytic cell, a galvanic slash voltaic cell, it doesn't matter. The cathode is always the site of reduction and the A note is always the site of oxidation. However, because electrolytic cells are non spontaneous, their signs will be different here. Since the process is non spontaneous, the cathode is now negatively charged, indiana is now positively charged. So basically our understanding here is that when it comes to electrolytic cells, they are the opposites of galvanic cells. So just remember this fundamental idea, they're opposites of one another.

Galvanic Cell (Simplified) Example 3

Here, it states, identify the location with an electrolytic cell where the loss of electrons will occur. Alright, so loss of electron means that we are undergoing oxidation. Yeah. Now remember, it doesn't matter what type of cell we're dealing with, whether it be an electrolytic cell. A galvanic cell will take. Cell. Oxidation always occurs at the A node, reduction always occurs at the cathode, so again, loss of electrons will occur at the anodes. That means that option B is the correct answer.

Galvanic Cell (Simplified) Concept 3

an electrolytic cell has to consume electrical energy in order to convert it into chemical energy. Now, in order to do this, it requires a battery. So one major difference between an electrolytic cell and a galvanic cell. Is that a galvanic cell itself is a battery that generates electricity. And an electrolytic cell requires a battery in order to work. Now, when it comes to an electrolytic cell, we still say that the cathode is the place of reduction. So electrons are still moving from the anodes towards the cathode and the piano itself, if it's losing electrons is the site of oxidation. Now, one difference here is that with an electrolytic cell is that we have our cathode being negative and our cathode being positive because of this, we can say that an electrolytic cell is non spontaneous. It's doing something that it really shouldn't be doing negative, electrons really don't want to head towards a place that's also negative. So those negative electrons are being forced to go to the negative cast out, that's why the battery is also required. It's the energy we need in order to force the electrons to go there. Now we're also going to say that our electrons are heading towards the cathode. And as before when we talked about galvanic cell, the same is true here, that the negative ion is heading towards the adult compartment and the positive ion is heading towards the cathode compartment. Now, if we look at the catholic compartment. Yes, it's negatively charged. But again, the Catheter is where reduction occurs. So here are 10, 2 ion is being reduced to tin solid. This would mean that our reaction would be tend to eye on a quiz, absorbs two electrons and in doing so becomes a solid. And then for the anote it's still where the site of oxidation occurs. So our copper sound is being oxidized to copper to ion. So here we have copper solid losing two electrons to become copper two plus ion plus the two electrons that it has released. Now remember our electrons will cancel out And we'll get our overall equation as our 10 to ion plus copper solid producing in solid Plus Copper two Plus acquis. Now what's the application of electrolytic cell? What we can say that an electrolytic cell we can find in examples of batteries such as a double A batteries, triple A batteries etcetera. And also it's a defining feature of rechargeable lithium batteries. So although we said that electrolytic cells can be thought of the opposite of galvanic cell. And that's true for a lot of reasons we can say that what binds them all together is that the anodes is the site of oxidation and the cathode is a site of reduction. So that's what our different electrochemical cells have in common. Other than that there is a lot different between a galvanic cell and an electrolytic cell. So keep in mind these features that we've talked for this particular type of electrochemical cell

Galvanic Cell (Simplified) Example 4

here, it says which of the following is true about an electrolytic cell. It changes chemical energy into electrical energy. No. What is the exact opposite? It harnesses the electrical energy from batteries and uses it to make chemical energy. It uses a positive cathode. Remember in this case, the cathode is negatively charged, not positive. It uses an electrical current to make a non spontaneous reaction. Go. Electrolytic cells are non spontaneous. They can't do the process naturally without the use of outside energy. Okay, So they're gonna have to siphon off this electrical energy from batteries. Use that energy to make themselves go and occur. So this year is true. He can't be all of the above because options A and B. We found were not true. So here we're going to say electrolytic cells are non spontaneous. As a result, they require an outside energy source Here. It happens in the form of batteries. We harness that electrical energy and use it to convert into chemical energy.

Which of the following statements is true for a salt bridge?

• A. Contains neutral atoms that interact with the ions in both half-cell compartments.
• B. Serves as a route through which ions can flow freely.
• C. Serves as the site of oxidation.
• D. Serves as the site of reduction.

Which of the following statements is TRUE for a voltaic cell, but FALSE for an electrolytic cell?

I. The flow of electrons is spontaneous.
II. Oxidation occurs at the anode.
III. Electrons flow from the anode to the cathode.

• A. Only I
• B. I and II
• C. II and III
• D. I, II, and III
• E. Only II

What is the balanced half reaction that occurs at the anode in the overall cell reaction of a voltaic cell?

3 MnO₄^–(aq) + 5 Fe(s) → 3 Mn²⁺(aq) + 5 Fe³⁺(aq)

• A. MnO₄^–(aq) + 8 H⁺(aq) + 5 e^– → Mn²⁺(aq) + 4 H₂O(l)
• B. 2 MnO₄^–(aq) + 12 H⁺(aq) + 6 e^– → 2 Mn²⁺(aq) + 3 H₂O(l)
• C. Fe(s) →Fe³⁺(aq) + 3 e^–
• D. Fe(s) →Fe²⁺(aq) + 2 e^–
• E. Fe²⁺(aq) → Fe³⁺(aq) + e^–