I am sorry I do not know what happens the symbolism, so I just deleted the symbols. Is it works for you that deleted the symbols?
Using standard reduction potentials, calculate the standard Ecell, emf, for each of the following reactions. State if each reaction is spontaneous or nonspontaneous. (Use the below reactions AS WRITTEN, DO NOT REARRANGE ANY REACTIONS.) You must show the two half-reactions and balance the gain and loss of electrons.
a. H2(g) + I2(s) -> 2H^1+(aq) + 2I^1-(aq)
b. Ni^2+(aq) + 2Ce^5+(aq) -> Ni(s) + 2Ce^4+(aq)
c. 4Ce^3+(aq) -> Ce(s) + 3Ce^4+(aq) (Acid solution)
d. 2Al^3+(aq) + 3Cd(s) -> 2Al(s) + 3Cd^2+(aq)
H2(g) ==> 2H^+(aq) + 2e..Eo = 0 v
I2(s) + 2e ==> 2I^-(aq)..Eo = +0.535 v
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H2(g) + I2(s) ==> 2H^+(aq) + 2I^-(aq)
Ecell as written = 0.535 v (0 + 0.535 = 0.535 v) and it is spontaneous since Ecell is positive. I have used each equation AS WRITTEN and I have not rearranged either half reaction; however, I think the problem contradicts itself in the first sentence. If I am to use standard reduction potentials then I must rearrange one of the half cells and that is forbidden in the problem. Anyway, you have the cell reaction as written, the cell potential as written, and that it is spontaneous as written. I hope this helps. The others are done the same way.
Thank you so so much!!!
To calculate the standard cell potential (Ecell) for each of the given reactions, you need to follow a few steps:
Step 1: Write the half-reactions for the oxidation and reduction processes involved in the reaction.
Step 2: Look up the standard reduction potentials (E°) for the half-reactions in a standard reduction potentials table.
Step 3: Determine the sign of each half-reaction based on the reduction potentials. The half-reaction with the more positive reduction potential will undergo reduction, and the other half-reaction will undergo oxidation.
Step 4: Balance the number of electrons transferred in each half-reaction so that they cancel out when combined.
Step 5: Add the two balanced half-reactions to obtain the overall balanced equation for the reaction.
Step 6: Calculate the standard cell potential (Ecell) by subtracting the reduction potential of the anode (oxidation half-reaction) from the reduction potential of the cathode (reduction half-reaction).
Step 7: Determine if the reaction is spontaneous or nonspontaneous based on the sign of the standard cell potential. If Ecell is positive, the reaction is spontaneous. If Ecell is negative, the reaction is nonspontaneous.
Now let's go through each reaction and apply these steps:
a. H2(g) + I2(s) → 2H^+(aq) + 2I^-(aq)
Half-reactions:
Oxidation: H2(g) → 2H^+(aq) + 2e^-
Reduction: I2(s) + 2e^- → 2I^-(aq)
Balance the electrons transferred:
Oxidation: H2(g) → 2H^+(aq) + 2e^-
Reduction: I2(s) + 2e^- → 2I^-(aq)
Combine the half-reactions:
H2(g) + I2(s) → 2H^+(aq) + 2I^-(aq)
Look up the standard reduction potentials (E°):
For the oxidation half-reaction (H2 → 2H^+ + 2e^-), E° = 0.00 V.
For the reduction half-reaction (I2 + 2e^- → 2I^-), E° = +0.54 V.
Calculate the standard cell potential (Ecell):
Ecell = E°cathode - E°anode
Ecell = (+0.54 V) - (0.00 V)
Ecell = +0.54 V (positive)
Based on a positive Ecell, the reaction is spontaneous.
Repeat the steps for the other reactions (b, c, and d) to determine their standard Ecell and spontaneity.