Question

1. Assuming these half reactions make a galvanic cell, what is the cell potential in volts.

𝐹2(𝑔) +2𝑒−→𝐹^−(𝑎𝑞)..........𝐸^o𝑟𝑒𝑑 = 2.87
𝐴𝑙^3+ +3𝑒−→𝐴𝑙(𝑠)..............𝐸^𝑜𝑟𝑒𝑑 = −1.66

2. What is the Gibbs Free energy for this galvanic cell in kJ/mol (hint: make sure your reaction is balanced correctly)

𝐹2(𝑔)+2𝑒−→𝐹−(𝑎𝑞)........𝐸^o𝑟𝑒𝑑 = 2.87
𝐴𝑙3++3𝑒−→𝐴𝑙(𝑠)............𝐸^o𝑟𝑒𝑑 = −1.66
3. Fill in the blank for the equilibrium constant (remember standard temperature is 25^oC):

ln(K) = _________________________

𝐹2(𝑔) +2𝑒−→𝐹−(𝑎𝑞)...........𝐸^o𝑟𝑒𝑑 = 2.87
𝐴𝑙^3+ +3𝑒−→𝐴𝑙(𝑠).............𝐸^o𝑟𝑒𝑑 = −1.66

Answer 1

I think I worked this earlier. See
https://www.jiskha.com/questions/1864203/assuming-these-half-reactions-make-a-galvanic-cell-what-is-the-cell-potential-in-volts

Answer 2

I tried doing the first one
1. Ecell = 1.66 + 2.87 = 4.53
2. deltaG = -nFEcell = - 2mol e-/1mol * 96485 * 4.53 = -874 KJ/mol but it was wrong. What did I do wrong here?
3. I don't know how to step that one up.

Answer 3

n is 6.
The balanced equation is
3*(F2 + 2e ==> 2F^-)
2*(Al ==> Al^3+ + 3e)

3F2 + 2Al --> Al^+3 + 6F^-