Cell Diagrams  [ENDORSED]

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ClaireHW
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Cell Diagrams

Postby ClaireHW » Mon Feb 19, 2018 7:36 pm

What are the rules for constructing a cell diagram? Order, inert metals, commas v. lines v. double lines, etc.

Thanks!

(Claire Woolson Dis 1K)

Julia Campbell 2F
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Re: Cell Diagrams

Postby Julia Campbell 2F » Mon Feb 19, 2018 8:33 pm

The anode half cell is described first, then the cathode half cell (so that as you read it, your eyes move in the direction of the electrons). Within a given half-cell, the reactants are specified first and the products last. A single vertical line is drawn between two chemical species that are in different phases but in physical contact with each other. A double vertical line represents a salt bridge or porous membrane separating the individual half-cells.

Rachel Formaker 1E
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Re: Cell Diagrams

Postby Rachel Formaker 1E » Mon Feb 19, 2018 8:35 pm

inert metal | reactant | product || reactant | product | inert metal

The anode is typically on the left and the cathode is typically on the right.
The double line represents the salt bridge, and will be replaced with a single line if there is a porous disk instead of a salt bridge.
Lines are used to separate substances in different states.
If there are substances in the same states, they will be separated by commas instead of lines in the order Ox,Red.
Inert metals are always the outermost component of either side.

Chem_Mod
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Re: Cell Diagrams  [ENDORSED]

Postby Chem_Mod » Wed Feb 21, 2018 11:40 am

The above answers are correct.
For cell diagram, within each half part, electrode and solids are written far away from the salt bridge, followed by liquid, gas and aqueous solution. Within each phase, orders are not strictly defined, but people tend to put in the order of reactant to product.

McKenna disc 1C
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Re: Cell Diagrams

Postby McKenna disc 1C » Wed Feb 21, 2018 4:00 pm

Rachel Formaker 1E wrote:inert metal | reactant | product || reactant | product | inert metal

The anode is typically on the left and the cathode is typically on the right.
The double line represents the salt bridge, and will be replaced with a single line if there is a porous disk instead of a salt bridge.
Lines are used to separate substances in different states.
If there are substances in the same states, they will be separated by commas instead of lines in the order Ox,Red.
Inert metals are always the outermost component of either side.


Referring to the order here: reactant | product || reactant | product
I feel like it also said in the book that it could be organized in terms of oxidized | reduced || oxidized | reduced (although I could be misremembering).
I'm getting the sense that whichever species goes in the left and right box WITHIN THE SAME SIDE of the double line isn't very rigidly enforced-- is that true? (i.e. is that something we'd be marked down for?)


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