Question 21.2: Write the reverse reaction for each reaction in Worked Examp...

Write the reverse reaction for each reaction in Worked Example 21.1. For each reverse reaction, determine ΔG and characterize the reaction as either exergonic or endergonic.
ANALYSIS First, remember that reactions are written left to right with the reaction arrow pointing to the right. Second, remember that the compounds that are products in the original reaction are reactants in the reverse reaction and the compounds that are reactants in the original reaction are products in the reverse reaction. (We are assuming the reaction is directly reversible; this is not always true inside cells.) Third, remember that if ΔG for the forward reaction is positive, ΔG for the reverse reaction has the same numeric value but is negative. If ΔG for the forward reaction is negative, ΔG for the reverse reaction has the same number value but is positive. Negative ΔG values indicate exergonic reactions, and positive ΔG values indicate endergonic reactions.