## Cathode and Anode

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MaryBanh_2K
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### Cathode and Anode

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?

Kevin Antony 2B
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### Re: Cathode and Anode

A cell can do work whenever Ecell > 0. This will always be the case if the Cathode is greater than the Anode.

Pablo 1K
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### Re: Cathode and Anode

Equilibrium not reached so it will continue if cathode Ecell greater than 0.

Emma Popescu 1L
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### Re: Cathode and Anode

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.

Osvaldo SanchezF -1H
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### Re: Cathode and Anode

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.

Rebekah Alfred 1J
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### Re: Cathode and Anode

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.

Jasmine Vallarta 2L
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### Re: Cathode and Anode

E(cell) = E(cathode) - E(anode); since we want E(cell) > 0, E(cathode) > E(anode)

005384106
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### Re: Cathode and Anode

What does the cathode and the anode do?

005384106
Posts: 101
Joined: Sat Aug 24, 2019 12:16 am

### Re: Cathode and Anode

Is the left side is the anode that dissolves, what happens to the right side (cathode)?

Kylie Lim 4G
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### Re: Cathode and Anode

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.

Vinita Saxena 2I
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### Re: Cathode and Anode

Electrons travel from cathode to anode, so cathode>anode means work is done.

Cindy Adiwidjaja 1B
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### Re: Cathode and Anode

The cell will continue to do work until it dies. So E has to be positive.

Brandon Valafar
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### Re: Cathode and Anode

A cell can do work when Ecell is greater than zero, meaning that the cathode must be greater than the anode.

Cindy Adiwidjaja 1B
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Joined: Sat Jul 20, 2019 12:15 am

### Re: Cathode and Anode

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.

Shail Avasthi 2C
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### Re: Cathode and Anode

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.

kendal mccarthy
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### Re: Cathode and Anode

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.

briannam_1F
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Joined: Wed Sep 18, 2019 12:18 am

### Re: Cathode and Anode

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."

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