Correct option is C
The given question requires calculating the standard free energy of hydrolysis of ATP at 25°C using the equilibrium constants provided.
Given Data:
Let's calculate the standard free energy of hydrolysis of ATP.
- Keq1=270K_{eq1} = 270Keq1 = 270 (for reaction 1)
- Keq2 = 890 (for reaction 2)
The relationship for equilibrium constant in coupled reactions: Keq=Keq1×Keq2K_{eq} = K_{eq1} \times K_{eq2}- Standard Gibbs free energy equation:ΔG∘=−RTlnKeq\Delta G^\circ = -RT \ln K_{eq}
- R=8.314R = 8.314R=8.314 J/mol·K
- T=298T = 298T=298 K (25°C)
- lnKeq\ln K_{eq}lnKeq needs to be computed.
The calculated standard free energy of hydrolysis of ATP at 25°C is approximately -30.7 kJ/mol.
Correct Answer:
Option 3: (-30 to -32) kJ/mol
Solution:
Using the Gibbs free energy equation:
ΔG∘=−RTlnKeq
Substituting the values:
ΔG∘=−(8.314×298)×ln(270×890)
ΔG∘≈−30.7 kJ/mol
Thus, the correct answer is option 3.