Anybody good at college chem?

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Basically can't figure this one out and haven't found shit for examples....
Yes I've searched google first but I'd like to think there are some chemistry knowledge inclined people out there. I'd like to know how to solve for the thing cause I've hit a brick wall.
The E[/i]°cell= +0.135 V for the reaction
3I2(s[/i]) + 5Cr2O72-(aq[/i]) + 34H+(aq[/i])
session.quest794225entrance1_N10030.mml
6IO3-(aq[/i]) + 10Cr3+(aq[/i]) + 17H2O
What is E[/i]cell if [Cr2O72-] = 0.027 M[/i], [H+] = 0.25 M[/i], [IO3-] = 0.00014 M[/i], and [Cr3+] = 0.0045 M[/i]?

 
3I2(s[/i]) + 5Cr2O72-(aq[/i]) + 34H+(aq[/i]) 6IO3-(aq[/i]) + 10Cr3+(aq[/i]) + 17H2O
What is E[/i]cell if [Cr2O72-] = 0.027 M[/i], [H+] = 0.25 M[/i], [IO3-] = 0.00014 M[/i], and [Cr3+] = 0.0045 M[/i]?
had an image for that
 
wow that got butchered in copy paste...
3I2(s[/i]) + 5Cr2O7(2-)(aq[/i]) + 34H+(aq[/i]) 6IO3(-)(aq[/i]) + 10Cr(3+)(aq[/i]) + 17H2O
What is E[/i]cell if [Cr2O7(2-)] = 0.027 M[/i], [H+] = 0.25 M[/i], [IO3(-)] = 0.00014 M[/i], and [Cr(3+)] = 0.0045 M[/i]?
 
well for standard potentials of reactions the equation is

E = E* - (R*T/nF)ln(Q) where Q is the reaction constant of the concentrations of your products and reactants... so Q = (Concentration Products)/(concentration reactants) remember to raise the concentrations to any powers like,
3Fe(aq) would be (concentration of Fe)^3 because of the number moles.
*** Q doesnt include solids.
T is your temp in kelvin
n is number of electrons that are used in the oxidation/reduction half reactions
F is a constant.. (Faraday's i believe) = 96,500
that should about do it
 
I haven't done inorganic stuff in a long time and forgot a bunch, but don't you have to go and look up a bunch of numbers for each of the compounds?
 
well the hint is First evaluate the net reaction in order to determine the number of electrons, n, involved. Next, write the equilibrium constant expression for the reaction. Finally, use the given information in the Nernst equation to calculate Ecell.so I've worked it like 4 ways and haven't got the right answer yetI've figured n is 30 and F is given for 96485 and R is 8.314 and the equation is
77fd93e90bedd188d9d0c0b65cfa49a5.png
so yeah like i said I've hit a wall
 
Well I know how to use the equation but with all this shit involved is where I hit a dead end. I think you have to use +0.135 V for Ecell or E* but can't figure this shit out
 
mainly the What is E[/i]cell if [Cr2O7(2-)] = 0.027 M[/i], [H+] = 0.25 M[/i], [IO3(-)] = 0.00014 M[/i], and [Cr(3+)] = 0.0045 M[/i]? partNot sure how that implements with the equation with the given information.
Sorry for so many posts but I have a test tomorrow and we learned this shit on friday and I've been going over it all weekend.
 
hope all that helped man, im off to bed, 8 am classes... good luck on the test. i got a 97 on that test, took it two weeks ago
 
so here's how my equation basically looks for it then
E= .135- (8.314*298/(30*96,485)xln(( 0.00014^6 x 0.0045^10)/(0.027^5 x 0.25^34))I got .151215the answer is actually 0.171017980910 V
WTF!!!!
 
I must've fucked up when I assumed the temperature was 298 since thats standard temp since it wasn't otherwise stated...... Fuck me right?
 
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