Question

For the reaction in which reactant A is converted to product B, the values of ΔH (kJ/mol) and ΔS (J/K.mol) for A are 54 and 22; and for B are 60 and 43. Which of the following statements is correct?

a) The reaction is endergonic.
b) The reaction is exergonic.
c) The reaction is at equilibrium.
d) The reaction is spontaneous

Answer 1

Without the temperature, we cannot determine if the reaction is spontaneous or not as the ΔG depends on both temperature and the given ΔH and ΔS values. Therefore, correct option is d.

Step-by-step explanation:

In determining whether the reaction where reactant A is converted to product B is spontaneous, we need to analyze the given thermodynamic values. The change in enthalpy (ΔH) and entropy (ΔS) for A are 54 kJ/mol and 22 J/K·mol, respectively; for B, these values are 60 kJ/mol and 43 J/K·mol, respectively.

To determine if the reaction is spontaneous, we use the Gibbs free energy equation, ΔG = ΔH - TΔS, whereby a negative ΔG indicates a spontaneous process. Without temperature data, we can't perform a numerical calculation, but because both ΔH and ΔS increase in the process of forming B from A, the sign of ΔG will depend on temperature.

At sufficiently high temperatures, the positive change in entropy (ΔS) could drive the reaction to be spontaneous. Therefore, none of the answers a), b), c), or d) can be determined as correct without additional information on temperature.

Answer 2

Without additional data such as the temperature at which the reaction takes place, we cannot accurately determine whether the reaction where reactant A is converted to product B is spontaneous, endergonic, or exergonic based on the given enthalpy and entropy changes.

The right answer is d) The reaction is spontaneous

Step-by-step explanation:

To determine whether the reaction in which reactant A is converted to product B is endergonic, exergonic, at equilibrium, or spontaneous, we need to consider both the changes in enthalpy (ΔH) and entropy (ΔS) for the reaction.

The enthalpy change for A is 54 kJ/mol and for B is 60 kJ/mol. The entropy change for A is 22 J/K·mol and for B is 43 J/K·mol.

The change in free energy (ΔG) for a process is given by the equation ΔG = ΔH - TΔS, where T is the temperature in Kelvin. A negative ΔG indicates a spontaneous reaction, while a positive ΔG suggests a nonspontaneous or endergonic reaction.

However, without information about the temperature or a direct comparison between the enthalpy and entropy changes of A and B at a specific temperature, we cannot definitively determine whether the reaction is spontaneous, endergonic, or exergonic.

Therefore, based on the given information, we cannot accurately select one of the provided statements without additional data such as the temperature at which the reaction takes place.

The right answer is d) The reaction is spontaneous