A student is given a standard galvanic cell, represented [VISUAL], that has a Cu electrode and a Sn — Thermodynamics Chemistry Question

Since the Sn electrode is losing mass, Sn atoms must be forming Sn²⁺(aq). This process is oxidation.
OR
because the cell operates, E° must be positive and, based on the E° values from the table, it must be Sn that is oxidized.

1 point is earned for the correct answer with justification.

The atoms on the Sn electrode are going into the solution as Sn²⁺ ions.

1 point is earned for the correct answer.

The response should show at least one K⁺ ion moving toward the Cu compartment on the left and at least one NO3− ion moving in the opposite direction.

1 point is earned for correct representation of both K⁺ and NO3− ions. (Including free electrons loses this point.)
1 point is earned for correctly indicating the direction of movement of both ions.

It is the same. In the cell reaction Q = [Sn²⁺]/[Cu²⁺], and the concentrations of Sn²⁺ and Cu²⁺ are equal to each other in both cases.

1 point is earned for the correct answer with justification. || The nonstandard cell would power the device for a shorter time because the supply of Cu²⁺ ions will be exhausted more quickly.
OR
The nonstandard cell would power the device for a shorter time because the reaction will reach E = 0 more quickly.

1 point is earned for the correct answer with justification.

Cu²⁺(aq) + Sn(s) → Cu(s) + Sn²⁺(aq)

E° is positive (0.34 V + 0.14 V = 0.48 V), therefore the reaction is thermodynamically favorable.
OR
The cell observations from earlier parts of the question are evidence that the Sn is oxidized and Cu is reduced, therefore E° must be positive.

1 point is earned for the correct net-ionic equation.
1 point is earned for a correct justification. || DG° = −nFE°
DG° = −(2 mol e−)(96,485 C/mol e−)(0.48 J/C) = −93,000 J/mol rxn = −93 kJ/mol rxn

1 point is earned for the correct number of electrons.
1 point is earned for the correct answer with unit.