So let's just compare our cells, side by side. Again, we said that the Galvanic cell, delta G, is negative. Meaning that it's spontaneous. The electrolytic cell, delta G, is positive, meaning it's non spontaneous. In both cases, we had our anode being oxidized and our cathode being reduced. Read full transcript
And we know that this is our anode on the Galvanic cell because it's losing the electrons. Same thing over here on the electrolytic cell. It's losing the electrons. So in both cells, electrons will flow from the anode to the cathode. The big difference is that, in the Galvanic cell, they flow freely.
In the electrolytic cell, we force them. And that makes all the difference. Since we have to force an electrolytic cell's reaction to happen, it means it is non-spontaneous. Unless we force it, it won't happen. Of the other difference, the charges on the anode and the cathode.
On the Galvanic cell, the anode is negative. On the electrolytic cell, it is positive. The cathode on the Galvanic cell is positive. And in the electrolytic cell, it is negative. Electrons will freely flow from negative to positive. But to get them to flow from positive to negative, we need to force them with a battery.