## calculating Q

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

805383532
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### calculating Q

When finding Q in the nernst equation, is it always [cathode]/[anode] or is it [anode]/[cathode] ?

Bilal Pandit 1J
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Joined: Wed Sep 11, 2019 12:16 am

### Re: calculating Q

It can be determined by the overall cell reaction, with the concentrations plugged in for Q (products over reactants)

Sjeffrey_1C
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Joined: Wed Feb 20, 2019 12:17 am

### Re: calculating Q

I believe its [anode]/[cathode]

Isabella Dal Porto 1H
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Joined: Fri Aug 30, 2019 12:16 am

### Re: calculating Q

I believe that it is [anode]/[cathode].

J_CHEN 4I
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Joined: Tue Nov 14, 2017 3:01 am

### Re: calculating Q

Q is [Products]/[Reactants] so it depends on the chemical equation.

AronCainBayot2K
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Joined: Fri Aug 30, 2019 12:17 am

### Re: calculating Q

Q should be anode/cathode.

Bryce Barbee
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Joined: Wed Sep 18, 2019 12:20 am

### Re: calculating Q

I was told that it is anode/cathode when using this equation.

saigorijavolu2k
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Joined: Sat Sep 28, 2019 12:15 am

### Re: calculating Q

anode/cathode

anode looses mass, cathode gains mass

Vivianvelazquez_1J
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Been upvoted: 1 time

### Re: calculating Q

It should be Anode over Cathode.

Trent Yamamoto 2J
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Joined: Sat Aug 17, 2019 12:18 am

### Re: calculating Q

Q= [anode]/[cathode]

Sean Cheah 1E
Posts: 105
Joined: Wed Sep 18, 2019 12:20 am

### Re: calculating Q

Q is a reaction quotient, which means that for most redox reactions, as long as you have the balanced equation, it should look identical to the equilibrium expression (with appropriate exponents to match the coefficients in the balanced equation). The equilibrium expression always puts products in the numerator and reactants in the denominator.

For example, looking at the generic redox equation A+(aq) + B (s) --> A(s) + B+(aq), the only concentration on the products' side is [B+] and the only concentration on the reactants' side is [A+]. Note that in this case, A+ is the species being reduced, meaning it is being consumed like a reactant at the cathode. Similarly, B(s) is the species being oxidized, meaning B+ is being produced like a product at the anode. Thus, since the coefficients are all 1 in this case, Q = [B+]/[A+] = [Anode ion]/[Cathode ion].

Alexandra Bartolome 2H
Posts: 102
Joined: Sat Jul 20, 2019 12:17 am

### Re: calculating Q

Q = [products]/[reactants] so it would be [anode]/[cathode]

Mariah
Posts: 104
Joined: Fri Aug 02, 2019 12:16 am

### Re: calculating Q

I think its easier to think products/reactants.

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