Cell X and Cell Y both operate under standard conditions and produce an identical…
CHEMISTRY · Single correct · A Level · Chemistry · Electrode potentials · Electrode potentials
Problem
Cell X and Cell Y both operate under standard conditions and produce an identical cell potential of 0.80V. In the balanced overall reaction for Cell X, 2 electrons are transferred, whereas in Cell Y, 4 electrons are transferred. Which statement best describes the relationship between their standard free-energy changes, ΔGX∘ and ΔGY∘?
(a) ΔGY∘ equals ΔGX∘ because free energy depends only on cell potential.
(b) ΔGY∘ is four times more negative than ΔGX∘ since both electrodes each add two extra electrons.
(c) ΔGY∘ is exactly twice as negative as ΔGX∘ because more electrons are transferred.
(d) ΔGY∘ is half as negative as ΔGX∘ because the electrons are split between two half-reactions.