Final answer:
The correct answer is B. A positive delta G' means that the reaction requires an input of energy and does not occur spontaneously; it is an endergonic reaction.
Step-by-step explanation:
Under the conditions of a given reaction, a positive ΔG' (delta G prime) indicates that the reaction in question is endergonic, meaning it requires an input of energy to proceed. It does not occur spontaneously and certainly implies that work will need to be done to drive the reaction forward. Therefore, the correct answer is: B. the reaction will not occur.
It is important to note that a positive ΔG' is associated with reactions where the products have more free energy than the reactants. Spontaneous reactions, in contrast, are ones where delta G is negative, and these are referred to as exergonic reactions, representing processes that release energy.
A reaction at equilibrium would have a delta G of zero, and a reaction that is spontaneous would have a negative delta G. Lastly, endergonic reactions such as the one described with a positive delta G will only occur if energy is added to the system.