Final answer:
The standard cell potential for each electrochemical cell is as follows: Part A: +2.12 V; Part B: +0.44 V; Part C: +0.62 V.
Step-by-step explanation:
To calculate the standard cell potential for each of the electrochemical cells, we need to use the standard reduction potentials for the half-reactions involved. The standard cell potential is the difference between the reduction potentials of the reduction half-reaction and the oxidation half-reaction.
Part A: The reduction half-reaction is Ni2+(aq) + 2e- → Ni(s) and the oxidation half-reaction is Mg(s) → Mg2+(aq) + 2e-. The standard reduction potential for Ni2+(aq) is -0.25 V and for Mg2+(aq) is -2.37 V. Therefore, the standard cell potential for Part A is -0.25 V - (-2.37 V) = +2.12 V.
Part B: The reduction half-reaction is 2H+(aq) + 2e- → H2(g) and the oxidation half-reaction is Fe(s) → Fe2+(aq) + 2e-. The standard reduction potential for H+(aq) is 0 V and for Fe2+(aq) is -0.44 V. Therefore, the standard cell potential for Part B is 0 V - (-0.44 V) = +0.44 V.
Part C: The reduction half-reaction is 2NO3-(aq) + 4H+(aq) + 3e- → 2NO(g) + 2H2O(l) and the oxidation half-reaction is Cu(s) → Cu2+(aq) + 2e-. The standard reduction potential for NO3-(aq) is +0.96 V and for Cu2+(aq) is +0.34 V. Therefore, the standard cell potential for Part C is +0.96 V - (+0.34 V) = +0.62 V.