Calculate the standard cell potential for each of the electrochemical cells?
2Ag+(aq)+Pb(s)→2Ag(s)+Pb2+(aq)
E∘cell......V?
2ClO2(g)+2I−(aq)→2ClO−2(aq)+I2(s)
E∘cell......V?
O2(g)+4H+(aq)+2Zn(s)→2H2O(l)+2Zn2+(aq)
E∘cell......V?
.93 volts, .41 volts, and 1.99 volts. I tried to find them out with "doctor" bobs way but I couldn't do them. My teacher did not even bother to teach us how to do this. For future reference Dr. Bob, instead of asking for one's work, how about at least show them where they could find these half reactions or something useful instead of wasting ones time.
To calculate the standard cell potential (E°cell) for each of the electrochemical cells, we can use the standard reduction potentials (E°red) of the species involved.
For the first reaction: 2Ag+(aq) + Pb(s) → 2Ag(s) + Pb2+(aq)
Step 1: Look up the standard reduction potentials for the reduction half-reactions involved.
- Ag+(aq) + e- → Ag(s) E°red = +0.80 V (reduction)
- Pb2+(aq) + 2e- → Pb(s) E°red = -0.13 V (oxidation)
Step 2: Reverse the oxidation half-reaction and add it to the reduction half-reaction.
- 2Ag+(aq) + Pb(s) → 2Ag(s) + Pb2+(aq)
Step 3: Add the two reduction potentials together to obtain the standard cell potential.
E°cell = E°red(reduction) + E°red(oxidation)
E°cell = (+0.80 V) + (-0.13 V)
E°cell = +0.67 V
Therefore, the standard cell potential for the first electrochemical cell is +0.67 V.
Now let's calculate the standard cell potential for the second electrochemical cell: 2ClO2(g) + 2I-(aq) → 2ClO-2(aq) + I2(s)
Step 1: Look up the standard reduction potentials for the reduction half-reactions involved.
- ClO2(g) + 2H+(aq) + 2e- → ClO-2(aq) + H2O(l) E°red = +1.08 V (reduction)
- I2(s) + 2e- → 2I-(aq) E°red = +0.54 V (oxidation)
Step 2: Reverse the oxidation half-reaction and add it to the reduction half-reaction.
- 2ClO2(g) + 2I-(aq) → 2ClO-2(aq) + I2(s)
Step 3: Add the two reduction potentials together to obtain the standard cell potential.
E°cell = E°red(reduction) + E°red(oxidation)
E°cell = (+1.08 V) + (+0.54 V)
E°cell = +1.62 V
Therefore, the standard cell potential for the second electrochemical cell is +1.62 V.
Lastly, we will calculate the standard cell potential for the third electrochemical cell: O2(g) + 4H+(aq) + 2Zn(s) → 2H2O(l) + 2Zn2+(aq)
Step 1: Look up the standard reduction potentials for the reduction half-reactions involved.
- O2(g) + 4H+(aq) + 4e- → 2H2O(l) E°red = +1.23 V (reduction)
- Zn2+(aq) + 2e- → Zn(s) E°red = -0.76 V (oxidation)
Step 2: Reverse the oxidation half-reaction and add it to the reduction half-reaction.
- O2(g) + 4H+(aq) + 2Zn(s) → 2H2O(l) + 2Zn2+(aq)
Step 3: Add the two reduction potentials together to obtain the standard cell potential.
E°cell = E°red(reduction) + E°red(oxidation)
E°cell = (+1.23 V) + (-0.76 V)
E°cell = +0.47 V
Therefore, the standard cell potential for the third electrochemical cell is +0.47 V.