General Chemistry, Standard voltage?

Question

mg^+2 +2e^- --> Mg

Cl2 +2e^- -->2Cl

write the equation and calculate E^0. Also what is E if Cl^- is .010M, Mg^+2 is .05M and Cl2=1.50 atm

Answer 1

Mg^+2 +2e^- --> Mg ....Eo = -2.37 volts  ( a reduction)

Cl2 +2e^- -->2Cl   ....  .Eo = +1.359 volts (also a reduction)

so turn the less positive voltage around:

Mg --> Mg +2e^-  ....Eo = + 2.37 volts  ( a reduction)

Cl2 +2e^- -->2Cl   ....  .Eo = +1.359 volts (also a reduction)

your first answer, the equation: Mg & Cl2  --> Mg+2  & 2 Cl-

your next answer, Eo = +3.73 volts

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Also what is E if Cl^- is .010M, Mg^+2 is .05M and Cl2=1.50 atm

nernst:

E = Eo - (0.0592 / n ) (log Q)

E = 3.73 volts  - (0.0592 / 2 mol e- ) (log prod / reactants)

E = 3.73 volts  - (0.0296 ) (log [Cl2] / [Mg+2] [Cl-]^2)

E = 3.73 volts  - (0.0296 ) (log [1.5] / [0.05] [0.01]^2)

E = 3.73 volts  - (0.0296 ) (log 300,000)

E = 3.73 volts  - (0.0296 ) 5.477

E = 3.73 volts  - 0.16

E = 3.57 volts