Can someone explain why the anode is positive and the cathode is negative in electrolytic cells?
Thanks in advance!
In any electrical circuit, the electrons flow from the positive to the negative terminal (direction of conventional current).
We also know that in any cell, whether galvanic or electrolytic, electrons flow from the anode, to the cathode.
To satisfy both of these facts, the anode must be positive, and the cathode negative, so electrons can flow from the anode to cathode. Don't forget that the anode is connected to the positive side of the battery, while cathode is connected to the negative side.
Galvanic cells don't require a battery, so the polarities are the opposite (electrons flow from anode to cathode, where anode is negative and cathode is positive).
I've attached two images below which should hopefully explain what I said a bit better.
Another question, in my book it says that the electron charge is -1.60*10^19C but when this concept is applied they changed the electron charge to 1.60*10^-19C(thus getting a +ve value), BUT when I checked the chem data book, the electron charge is noted to be -1.60*10^-19C, so now I am confused of which one to use? obviously, I would rely on the value in the data book right? but why are the charges so different?
Thanks in advance!
I'm not really sure where that first value comes from, so I won't answer for that but 1.60*10^-19 is the charge of an electron (and the value in the Physics data sheet.). The -1.60*10^-19 value just notes that the charge of an electron is negative. Using 1.60*10^-19 is accurate and you can use this, but just make sure to keep in mind that the charge of the electron is negative.
Hope this helps, let me know if you have any other questions