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The EMF of a Daniel cell at 298 K298\text{ K} is E1E_1: ZnZnSO4(0.01 M)CuSO4(1.0 M)CuZn|ZnSO_4(0.01\text{ M}) || CuSO_4(1.0\text{ M})|Cu. When the concentration of ZnSO4ZnSO_4 is 1.0 M1.0\text{ M} and that of CuSO4CuSO_4 is 0.01 M0.01\text{ M}, the EMF is changed to E2E_2. The correct relationship between E1E_1 and E2E_2 is:

A

E1>E2E_1 > E_2

B

E1<E2E_1 < E_2

C

E1=E2E_1 = E_2

D

E2=0E1E_2 = 0 \neq E_1

Step-by-Step Solution

The cell reaction for a Daniell cell is: Zn(s)+Cu2+(aq)Zn2+(aq)+Cu(s)Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s)

According to the Nernst equation at 298 K298\text{ K}: Ecell=Ecell0.05912log[Zn2+][Cu2+]E_{cell} = E^{\circ}_{cell} - \frac{0.0591}{2} \log \frac{[Zn^{2+}]}{[Cu^{2+}]}

For the first case (E1E_1): [Zn2+]=0.01 M=102 M[Zn^{2+}] = 0.01\text{ M} = 10^{-2}\text{ M} and [Cu2+]=1.0 M[Cu^{2+}] = 1.0\text{ M} E1=Ecell0.05912log(1021)=Ecell0.05912(2)=Ecell+0.0591 VE_1 = E^{\circ}_{cell} - \frac{0.0591}{2} \log \left(\frac{10^{-2}}{1}\right) = E^{\circ}_{cell} - \frac{0.0591}{2} (-2) = E^{\circ}_{cell} + 0.0591\text{ V}

For the second case (E2E_2): [Zn2+]=1.0 M[Zn^{2+}] = 1.0\text{ M} and [Cu2+]=0.01 M=102 M[Cu^{2+}] = 0.01\text{ M} = 10^{-2}\text{ M} E2=Ecell0.05912log(1102)=Ecell0.05912(2)=Ecell0.0591 VE_2 = E^{\circ}_{cell} - \frac{0.0591}{2} \log \left(\frac{1}{10^{-2}}\right) = E^{\circ}_{cell} - \frac{0.0591}{2} (2) = E^{\circ}_{cell} - 0.0591\text{ V}

Comparing E1E_1 and E2E_2, we get E1>E2E_1 > E_2.

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