Table of standard electrode potentials
-Using a table of standard electrode potentials, decide which of the following statements is completely true.

Question

Table of standard electrode potentials 
-Using a table of standard electrode potentials, decide which of the following statements is completely true.

Quizplus · Accepted Answer

Additional information for each answer choice :A: If Cl₂ can oxidize Cd, then Cl₂ would be reduced and Cd would be oxidized. This results in the following reactions:Cl₂(g)+ 2e^- ? 2Cl^-(aq)E° = +1.36Cd(s)? Cd²⁺(aq)+ 2e^- E° = -(-0.40)(Sign switched for oxidation)Which gives a potential of +0.96 V, so this is spontaneous and should happen.If Al can reduce Cu²⁺, then Al would be oxidized and Cu²⁺ would be reduced. This results in the following reactions:Al(s)? Al³⁺(aq)+ 3e^- E° = -(-1.66)(Sign switched for oxidation)Cu²⁺(aq)+ 2e^-? Cu(s)E° = +0.34Which gives a potential of +2.00 V, so this is spontaneous and should happen. B: If Cd²⁺ can oxidize Cu, then Cd²⁺ would be reduced and Cu would be oxidized. This results in the following reactions:Cd²⁺(aq)+ 2e^- ? Cd(s)E° = -0.40Cu(s)? Cu²⁺(aq)+ 2e^- E° = -(0.34)(Sign switched for oxidation)Which gives a potential of -0.74 V, so this is not spontaneous and should not happen.If Cd²⁺ can reduce Cl₂, then Cd²⁺ would be oxidized and Cl₂ would be reduced. This results in the following reactions:Cd(s)? Cd²⁺(aq)+ 2e^- E° = -(-0.40)(Sign switched for oxidation)Cl₂(g)+ 2e^- ? 2Cl^-(aq)E° = +1.36Which gives a potential of +1.76 V, so this is spontaneous and should happen.But, because the first is not true, then this option is not correct. C: If Cu²⁺ can oxidize Cd, then Cu²⁺ would be reduced and Cd would be oxidized. This results in the following reactions:Cu²⁺(aq)+ 2e^- ? Cu(s)E° = -0.34Cd(s)? Cd²⁺(aq)+ 2e^- E° = -(-0.40)(Sign switched for oxidation)Which gives a potential of +0.06 V, so this is spontaneous and should happen.If Cd can reduce Al³⁺, then Cd would be oxidized and Al³⁺ would be reduced. This results in the following reactions:Cd(s)? Cd²⁺(aq)+ 2e^- E° = -(-0.40)(Sign switched for oxidation)Al³⁺(aq)+ 3e^- ? Al(s)E° = -1.66Which gives a potential of -1.26 V, so this is not spontaneous and should not happen.Because the second is not true, then this option is not correct.

Table of Standard Electrode Potentials