Salt Bridges

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Grace Boyd 2F
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Salt Bridges

Postby Grace Boyd 2F » Mon Feb 05, 2018 6:01 pm

What exactly do salt bridges do? I'm sort of struggling with this concept. Thank you!

Jack Papciak 2F
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Re: Salt Bridges

Postby Jack Papciak 2F » Mon Feb 05, 2018 6:03 pm

A salt bridge allows for ion transfer between the two solutions, and this allows for the two solutions to stay neutral.

aTirumalai-1I
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Re: Salt Bridges

Postby aTirumalai-1I » Mon Feb 05, 2018 8:34 pm

Without a salt bridge to manage the unequal charges, the electrons flowing to the cathode will eventually stop because the buildup will cause electron-electron repulsion. Likewise, the anode would have such a high positive charge that it will want to hold on to the negative electrons.

Yutian Zhao -1J
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Re: Salt Bridges

Postby Yutian Zhao -1J » Sat Feb 10, 2018 3:10 pm

salt bridges are designed to make a complete electrical circuit. Without the salt bridges, as anode keeps losing e-, it becomes less negative, and as cathode keeps accepting e-, it becomes less positive; after a period of time, anode and cathode go to equilibrium and become neutral where no e- will be transferred since the potential difference would be 0 at equilibrium. As a result, salt bridges provide negative ions to anode to keep it negative and provide positive ions to cathode to keep it positive. Hope it helps!

Julie Steklof 1A
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Re: Salt Bridges

Postby Julie Steklof 1A » Sat Feb 10, 2018 3:30 pm

A salt bridge serves to keep the charges between the two solutions to remain neutral and for the redox reaction to continue.

RussellChin_3A
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Re: Salt Bridges

Postby RussellChin_3A » Sat Feb 10, 2018 3:42 pm

As the e- current transfers from the anode to the cathode, the ion in the anode loses the e- to the cathode making the anode gradually positive and the cathode gradually negative. Because of this, the cell will gradually stop receiving e- from the anode because it was already negative. The salt bridge allows the transfer of other ions such as Cl- to the anode so that it keeps the charges on each side balanced. As Cl- moves to the anode, it balances out the positive charge of the anode as the e- moves to the cathode.

Michelle Lee 2E
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Re: Salt Bridges

Postby Michelle Lee 2E » Sat Feb 10, 2018 11:34 pm

In the anode, electrons are taken away to be put in the cathode. This makes the anode solution more positive and the cathode solution more negative. Since electrons are also negative, if the negativity of the cathode builds up, then it would start rejecting the electrons (negatives repulse negatives). The salt bridge helps in this case. It transfers negative ions like Cl- from the cathode solution to the anode solution to balance out the change in charge.
There are also diagrams where the salt bridge gives the cathode positive ions like Na+ and gives the anode negative ions like Cl-, is this how salt bridges work? (Because in lecture, the diagram of the battery was always drawn with the salt bridge transferring negative ions from the cathode to the anode.)

Michael Cheng 1C
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Re: Salt Bridges

Postby Michael Cheng 1C » Sun Feb 11, 2018 12:51 am

does a porous disk and salt bridge have the same purpose?

Guangyu Li 2J
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Re: Salt Bridges

Postby Guangyu Li 2J » Sun Feb 11, 2018 5:10 pm

A salt bridge is a connection of between the oxidation and reduction half-cells of a galvanic cell. It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium. In other words, only if a salt bridge is present, electricity can be produced in the galvanic cell.

Hope this helps! Have a good weekend!

Magdalena Palavecino 1A
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Re: Salt Bridges

Postby Magdalena Palavecino 1A » Wed Feb 14, 2018 10:19 pm

How would the charges of each side be balanced using a porous disk? Also, a single line in the shorthand equation serves as a porous disk too instead of two lines signifying a salt bridge, and when the reactants and products of one half equation are in the same state you separate them by a comma.

melissa carey 1f
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Re: Salt Bridges

Postby melissa carey 1f » Thu Feb 15, 2018 9:10 am

In a battery, like a AAA battery, what serves as a salt bridge?

Kayla Tchorz-Dis 1F
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Re: Salt Bridges

Postby Kayla Tchorz-Dis 1F » Fri Feb 16, 2018 2:27 pm

Salt bridges are used to transfer electrons that have already passed from the anode, to the cathode, back to the anode. This maintains equilibrium in the battery and allows it to not “die” as fast.

Michael Lee 2I
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Re: Salt Bridges

Postby Michael Lee 2I » Fri Feb 16, 2018 3:55 pm

The salt bridge keeps the two solutions neutral so that the redox reaction can continue.

Meredith Steinberg 2E
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Re: Salt Bridges

Postby Meredith Steinberg 2E » Fri Feb 16, 2018 5:39 pm

Salt bridges keep both solutions neutral as reduction and oxidation are occurring

Mitch Walters
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Re: Salt Bridges

Postby Mitch Walters » Fri Feb 16, 2018 7:19 pm

Salt bridges allow electron transfer between two solutions.


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