## Finding Q

$E_{cell} = E_{cell}^{\circ}-\frac{RT}{nF}\ln Q$

TimVintsDis4L
Posts: 104
Joined: Sat Aug 17, 2019 12:17 am

### Finding Q

When we are given a Cell Diagram and concentrations and asked to find the Q what do we use as the Products and Reactants. Would we not use the right side (cathode, reduced) side as the Product and the (anode,oxidized) side as the Reactant?

Renee Grange 1I
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Joined: Fri Aug 30, 2019 12:16 am
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### Re: Finding Q

You can write the total reaction to see what the products and reactions are. But, I believe the anode is usually the product and the cathode usually the reactant.

Brooke Yasuda 2J
Posts: 102
Joined: Sat Jul 20, 2019 12:17 am

### Re: Finding Q

Yes, the anode is the product and the cathode is the reactant. This makes sense because in the anode the concentrations of reactant are decreasing as it forms product in the cathode.

Mandeep Garcha 2H
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

### Re: Finding Q

Q=anode/cathode. So you can plug in all the values you know for the equation and solve for the unknown.

Anthony Hatashita 4H
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Joined: Wed Sep 18, 2019 12:21 am

### Re: Finding Q

Q is anode/cathode usually. You can write out the full reaction equation to verify on a case to case basis.

Sanjana Borle 2K
Posts: 111
Joined: Fri Aug 09, 2019 12:15 am

### Re: Finding Q

Since you flip the equation for the anode when writing out the total equation for a cell, it makes sense that Q would be anode/cathode because this way the anode becomes the product.

Juana Abana 1G
Posts: 100
Joined: Wed Sep 18, 2019 12:15 am

### Re: Finding Q

Brooke Yasuda 2J wrote:Yes, the anode is the product and the cathode is the reactant. This makes sense because in the anode the concentrations of reactant are decreasing as it forms product in the cathode.

So then the anode is always the product and the cathode is always the reactant?

Jasmine Kim 1L
Posts: 71
Joined: Fri Aug 02, 2019 12:16 am

### Re: Finding Q

Juana Abana 1G wrote:So then the anode is always the product and the cathode is always the reactant?

In most cases, yes, but I would always write out the reaction to be sure.

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