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Cathode and Anode

Posted: Thu Mar 05, 2020 6:34 pm
by MaryBanh_2K
Why can we assume the cell can do work when the E value at the Cathode is bigger than the E value at the Anode?

Re: Cathode and Anode

Posted: Thu Mar 05, 2020 6:40 pm
by Kevin Antony 2B
A cell can do work whenever Ecell > 0. This will always be the case if the Cathode is greater than the Anode.

Re: Cathode and Anode

Posted: Thu Mar 05, 2020 7:05 pm
by Pablo 1K
Equilibrium not reached so it will continue if cathode Ecell greater than 0.

Re: Cathode and Anode

Posted: Sat Mar 07, 2020 10:02 pm
by Emma Popescu 1L
The work done by the cell is is equal to the change in gibbs free energy. Based on the equation deltaG=-nFE, E needs to be positive so that energy is released (deltaG is negative) and thus the cell does work.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 3:51 am
by Osvaldo SanchezF -1H
Well for an E cell to do work its value has to positive. To find the value for cell potential it would be Ecathode - Eanode and so if cathode is larger then it will yield a positive value.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 9:28 am
by Rebekah Alfred 1J
My TA mentioned that E cell can be negative sometimes and I believe there is a question with a negative E cell in section 6N.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 10:55 am
by Jasmine Vallarta 2L
E(cell) = E(cathode) - E(anode); since we want E(cell) > 0, E(cathode) > E(anode)

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 1:09 pm
by 005384106
What does the cathode and the anode do?

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 1:17 pm
by 005384106
Is the left side is the anode that dissolves, what happens to the right side (cathode)?

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 1:54 pm
by Kylie Lim 4G
From the equation deltaG = -nFE, you can tell that a reaction is spontaneous and does work if the value of Ecell > 0. Since to find E you would subtract the potential of the cathode by the potential of the anode, you will always get Ecell > 0 if the cathode value is larger.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 3:06 pm
by Vinita Saxena 2I
Electrons travel from cathode to anode, so cathode>anode means work is done.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 9:57 pm
by Cindy Adiwidjaja 1B
The cell will continue to do work until it dies. So E has to be positive.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 10:00 pm
by Brandon Valafar
A cell can do work when Ecell is greater than zero, meaning that the cathode must be greater than the anode.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 11:24 pm
by Cindy Adiwidjaja 1B
It is just standard convention that we travel from the anode to the cathode. When a cell is working spontaneously and naturally, then it will always travel from left to right.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 11:31 pm
by Shail Avasthi 2C
Because if there is still potential difference between the cathode and anode, then the reaction is not at equilibrium, and electrons will continue to flow from the cathode to the anode. This generates electricity.

Re: Cathode and Anode

Posted: Sun Mar 08, 2020 11:36 pm
by kendal mccarthy
This is because the Evalue at the cathode basically determines if the Ecell will be positive or negative. When the value is positive the system can do work, when the value is negative work must be done on the system. The equation is Ecell=Ecath-Eannode, so if Ecath>Eanode, the equation will have a net positive value.

Re: Cathode and Anode

Posted: Tue Mar 17, 2020 9:35 pm
by briannam_1F
We want the ECell to be positive in order to do work because once the Ecell is equal to zero then that is when the battery is considered to be "dead."