arrow
arrow
arrow
For the coupled reaction given below, the equilibrium constants (Keq)(K_{eq})(Keq​) for equation [1][1][1] and equation [2][2][2] are 270 and 890
Question

For the coupled reaction given below, the equilibrium constants 

(Keq)(K_{eq})(Keq) for equation [1][1][1] and equation [2][2][2] are 270 and 890, respectively.

Glucose 6-phosphate+H2O→Glucose+Pi[1]\text{Glucose 6-phosphate} + H_2O \rightarrow \text{Glucose} + P_i \quad [1]Glucose 6-phosphate+H2OGlucose+Pi[1]ATP+Glucose→ADP+Glucose 6-phosphate[2]\text{ATP} + \text{Glucose} \rightarrow \text{ADP} + \text{Glucose 6-phosphate} \quad [2]

ATP+GlucoseADP+Glucose 6-phosphate[2]

The standard free energy of hydrolysis of ATP at 25°C is:

A.

(-24 to -26) kJ/mol

B.

(-18 to -20) kJ/mol

C.

(-30 to -32) kJ/mol

D.

(-60 to -62) kJ/mol

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}Keq=Keq1×Keq2K_{eq} = K_{eq1} \times K_{eq2}
  • Standard Gibbs free energy equation:ΔG∘=−RTln⁡Keq\Delta G^\circ = -RT \ln K_{eq}
     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)
    • ln⁡Keq\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.​




Similar Questions

test-prime-package

Access ‘CSIR NET Life Sciences’ Mock Tests with

  • 60000+ Mocks and Previous Year Papers
  • Unlimited Re-Attempts
  • Personalised Report Card
  • 500% Refund on Final Selection
  • Largest Community
students-icon
368k+ students have already unlocked exclusive benefits with Test Prime!
test-prime-package

Access ‘CSIR NET Life Sciences’ Mock Tests with

  • 60000+ Mocks and Previous Year Papers
  • Unlimited Re-Attempts
  • Personalised Report Card
  • 500% Refund on Final Selection
  • Largest Community
students-icon
368k+ students have already unlocked exclusive benefits with Test Prime!
Our Plans
Monthsup-arrow