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For the reaction below, what is the Δg° at 298 K?

User Pomeroy
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1 Answer

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Final answer:

To calculate the standard Gibbs free energy change (ΔG°) at 298 K, we use the formula ΔG° = ΔH° - TΔS° with the provided values to obtain ΔG° = 130.0 kJ/mol, suggesting the reaction is nonspontaneous at this temperature.

Step-by-step explanation:

The standard Gibbs free energy change (ΔG°) at 298 K for a reaction can be calculated using the formula:

ΔG° = ΔH° - TΔS°

where ΔH° is the standard enthalpy change, T is the temperature in Kelvin (K), and ΔS° is the standard entropy change. Using the given values:

ΔG° = 177.8 kJ/mol - 298 K * (0.1605 kJ/K mol)

Substitute the values into the equation:

ΔG° = 177.8 kJ/mol - (298 K * 0.1605 kJ/K mol)

The calculation gives:

ΔG° = 177.8 kJ/mol - 47.83 kJ/mol = 129.97 kJ/mol or approximately 130.0 kJ/mol

The positive value of ΔG° indicates that the reaction is nonspontaneous under standard conditions at 298 K and favors the reactants.

User Arunachalam K
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