For the two reactions (a) A → B ∆G°′ = 2 kJ mol⁻¹, and (b) X → Y ∆G°′ = −3.5 kJ mol⁻¹ , which of the following statements is correct? A) Reaction (a) is not spontaneous at cellular concentrations. B) Reaction (b) will react very quickly. C) Reaction (a) is a more thermodynamically favorable reaction than is (b). D) Neither reaction is reversible. E) None of the above.

Question

Quizplus · Accepted Answer

The sign of ∆G°′ determines spontaneity, not speed or reversibility. Reaction (a) has a positive ∆G°′, indicating it is not spontaneous under standard conditions, while reaction (b) has a negative ∆G°′, indicating it is spontaneous under standard conditions. However, spontaneity does not directly correlate with reaction speed, nor does it imply irreversibility.

For the Two Reactions (A) a → B ∆G°′ =