Question

A critical reaction in the production of energy to do work or drive chemical reactions in biological systems is the hydrolysis of adenosine triphosphate, ATP, to adenosine diphosphate, ADP, as described by the reaction ATP(aq)+H2O(l)⟶ADP(aq)+HPO2−4(aq) for which Δ????∘rxn=−30.5 kJ/mol at 37.0 °C and pH 7.0. Calculate the value of Δ????rxn in a biological cell in which [ATP]=5.0 mM, [ADP]=0.50 mM, and [HPO2−4]=5.0 mM.

Answer 1

-50.09 kJ/mol

Step-by-step explanation:

Let ΔGrxn be

ΔGrxn = ΔGrxn° + RT ln{[ADP][HPO₄²⁻]/[ATP]}

Given:

ΔGrxn = -30.5 × 10³

R = 8.314

T = 37°c = 310k

[ATP] = (5.0 × 10⁻³) M,

[ADP] = (0.50 × 10⁻³) M,

[HPO₄²⁻] = (5.0 × 10⁻³) M :

We have:

ΔGrxn

= (-30.5 × 10³) + (8.314) × (310) × ln{(0.50 × 10⁻³) × (5.0 × 10⁻³) / (5.0 × 10⁻³)} J/mol

= −50,090 J/mol

= -50.09 kJ/mol