How to write Cell Diagrams

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Baoying Li 1B
Posts: 113
Joined: Sat Aug 17, 2019 12:18 am

How to write Cell Diagrams

Postby Baoying Li 1B » Fri Feb 21, 2020 10:57 pm

Can somebody list the steps of writing a cell diagram?

Connie Chen 1E
Posts: 51
Joined: Mon Jun 17, 2019 7:24 am

Re: How to write Cell Diagrams

Postby Connie Chen 1E » Fri Feb 21, 2020 11:44 pm

The basic structure of a cell diagram is (left) anode || (right) cathode, where || represents a salt bridge. You want to put the substance being oxidized on the left and and the substance being reduced on the right so that the voltage is positive. Within the left or right side, you want to write out all the substances that are there and use | to show an interface between phases in contact. So if you have copper in solid form and copper in aqueous form, you would use | to separate them.

Ryan Yoon 1L
Posts: 55
Joined: Mon Jul 01, 2019 12:15 am

Re: How to write Cell Diagrams

Postby Ryan Yoon 1L » Sat Feb 22, 2020 12:10 am

The || represents the salt bridge and | is the interphase between phases in contact. The basic structure is cathode(REDUCTION)||anode(OXIDATION).

Orrin Zhong 4G
Posts: 51
Joined: Sat Jul 20, 2019 12:16 am

Re: How to write Cell Diagrams

Postby Orrin Zhong 4G » Sat Feb 22, 2020 12:19 am

I would also like to add that if a porous disc/wall is replacing the salt bridge, the separation between the anode and cathode is denoted by only one "|". Also, I'm not sure if this is a strict rule, but by convention, you place the conducting electrodes on the outsides of the cell diagram and you place the reactants and products that are in solution on the insides of the cell diagram, surrounding the midline separating the cathode and the anode. This is an example from Lavelle's lecture in today: "Cu(s) | Cu2+(aq) || Fe3+(aq), Fe2+(aq) | Pt(s)" for the reaction "2 Fe3+(aq) + Cu(s) --> Cu2+(aq) + 2Fe2+(aq)".

Altamash Mahsud 1I
Posts: 50
Joined: Fri Aug 09, 2019 12:16 am

Re: How to write Cell Diagrams

Postby Altamash Mahsud 1I » Sat Feb 22, 2020 2:51 am

To write a cell diagram, you must keep in mind that for convention (most of the time), the left side of the cell diagram is the anode, and the right side of the cell diagram is the cathode. You write all the solid metals (electrodes) on the outer most parts of both the left side and the right side (which means all the way on the left and right). Then depending on whether or not there are aqueous solutions, gases, or both, put those next to the solids on their respective sides, separated by one straight vertical line. To separate the two sides of the galvanic cell, you put two vertical lines.

Angela Prince 1J
Posts: 102
Joined: Sat Aug 24, 2019 12:17 am

Re: How to write Cell Diagrams

Postby Angela Prince 1J » Sat Feb 22, 2020 11:12 am

Connie Chen 1E wrote:The basic structure of a cell diagram is (left) anode || (right) cathode, where || represents a salt bridge. You want to put the substance being oxidized on the left and and the substance being reduced on the right so that the voltage is positive. Within the left or right side, you want to write out all the substances that are there and use | to show an interface between phases in contact. So if you have copper in solid form and copper in aqueous form, you would use | to separate them.


Because the Fe3+ and the Fe2+ from the example in class yesterday are both in the aqueous phase, is that why they are only separated by a comma?


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