Balance the following skeleton reaction, calculate E o cell , and state whether the reaction is spontaneous: Cu+(aq) + PbO2(s) + SO42−(aq) → PbSO4(s) + Cu2+(aq) [acidic] Write the balanced equation, making sure to include the state of each component. E o cell = V Is the reaction spontaneous or nonspontaneous? spontaneous nonspontaneous

Respuesta :

Answer:

[tex]2Cu^++PbO_2+SO_4^{2-}+4H^+\rightarrow 2Cu^{2+}+PbSO_4+2H_2O[/tex]

[tex]E^0=1.53[/tex], the reaction is spontaneous.

Explanation:

Oxidation reaction is defined as the chemical reaction in which an atom looses its electrons. The oxidation number of the atom gets increased during this reaction.

[tex]X\rightarrow X^{n+}+ne^-[/tex]

Reduction reaction is defined as the chemical reaction in which an atom gains electrons. The oxidation number of the atom gets reduced during this reaction.

[tex]X^{n+}+ne^-\rightarrow X[/tex]

For the given chemical reaction:

[tex]Cu^++PbO_2+SO_4^{2-}\rightarrow PbSO_4+Cu^{2+}[/tex]

The half cell reactions for the above reaction follows:

Oxidation half reaction:  [tex]Cu^+\rightarrow Cu^{2+}+e^-[/tex]

Reduction half reaction:  [tex]PbO_2+SO_4^{2-}+4H^++2e^-\rightarrow PbSO_4+2H_2O[/tex]

To balance the oxidation half reaction must be multiplied by 2 and thus, the balanced equation is:-

[tex]2Cu^++PbO_2+SO_4^{2-}+4H^++2e^-\rightarrow 2Cu^{2+}+PbSO_4+2H_2O[/tex]

Here [tex]Cu^+[/tex]  undergoes oxidation by loss of electrons, thus act as anode. [tex]PbO_2[/tex]  undergoes reduction by gain of electrons and thus act as cathode.

[tex]E^0=E^0_{cathode}- E^0_{anode}[/tex]

Where both [tex]E^0[/tex] are standard reduction potentials.

[tex]E^0_{[Cu^{2+}/Cu^{+}]}= +0.16V[/tex]

[tex]E^0_{[PbO_2/PbSO_4]}=+1.69V[/tex]

[tex]E^0=E^0_{[PbO_2/PbSO_4]}- E^0_{[Cu^{2+}/Cu^{+}]}[/tex]

[tex]E^0=+1.69- (0.16V)=1.53[/tex]

Since, [tex]E^0>0[/tex], the reaction is spontaneous.