Step 1: Daniell Cell Description.
A Daniell cell is an electrochemical cell. It comprises a zinc electrode immersed in a zinc sulfate solution and a copper electrode immersed in a copper sulfate solution. The overall reaction within a Daniell cell is:\[\text{Zn}(s) + \text{CuSO}_4(aq) \rightarrow \text{ZnSO}_4(aq) + \text{Cu}(s)\]In this reaction, zinc undergoes oxidation at the anode by losing electrons, and copper ions undergo reduction at the cathode by gaining electrons.
Step 2: Evaluation of Options.
- (1) \( \text{Zn}(aq) + \text{CuSO}_4(aq) \rightarrow \text{ZnSO}_4(aq) + \text{Cu}(aq) \): This option is incorrect because zinc is in a solid state, not aqueous. - (2) \( \text{ZnSO}_4(s) + \text{Cu} \rightarrow \text{CuSO}_4(aq) + \text{Zn}(aq) \): This option is incorrect as it does not represent a Daniell cell and features erroneous states of matter. - (3) \( \text{Zn}(s) + \text{CuSO}_4(aq) \rightarrow \text{ZnSO}_4(aq) + \text{Cu}(s) \): This is the correct representation of the Daniell cell reaction. - (4) \( \text{ZnSO}_4(aq) + \text{Cu} \rightarrow \text{CuSO}_4(aq) + \text{Zn}(s) \): This option is incorrect and does not represent a Daniell cell.
Step 3: Determination.
Consequently, the accurate reaction for a Daniell cell is identified as option (3):\[\text{Zn}(s) + \text{CuSO}_4(aq) \rightarrow \text{ZnSO}_4(aq) + \text{Cu}(s)\]
\(Pt(s) ∣ H2(g)(1atm) ∣ H+(aq, [H+]=1)\, ∥\, Fe3+(aq), Fe2+(aq) ∣ Pt(s)\)
Given\( E^∘_{Fe^{3+}Fe^{2+}}\)\(=0.771V\) and \(E^∘_{H^{+1/2}H_2}=0\,V,T=298K\)
If the potential of the cell is 0.712V, the ratio of concentration of \(Fe2+\) to \(Fe3+\) is