Chapter 6, Problem 6.15NP

(a)

Interpretation Introduction

Interpretation:

The value of $\Delta G^0$ for the biological synthesis of ammonia at $298\text{ K}$ should be calculated.

Concept Introduction :

For a general reaction as follows:

  $\text{Reactant}\to \text{Product}$

The value of change in Gibbs free energy of a reaction is calculated as follows:

  $\Delta G_R={\displaystyle \sum \Delta G_f(\text{Products) - }{\displaystyle \sum \Delta G_f(\text{Reactants)}}}$

(b)

Interpretation Introduction

Interpretation:

The equilibrium constant for the biological synthesis of ammonia at $298\text{ K}$ should be calculated.

Concept Introduction :

The change in Gibbs free energy of the reaction can be calculated from the equilibrium constant as follows:

  $\Delta G_R=-RT\ln K_P$

Here,

  $\begin{array}{l}\Delta G_R\text{ - Gibbes free energy change}\\ R\text{ - universal gas constant}\\ T\text{ - temperature}\\ K_P\text{- equilibrium constant}\end{array}$

(c)

Interpretation Introduction

Interpretation:

Whether the pathway is spontaneous should be determined.

Concept Introduction :

Spontaneity of a reaction can be predicted by the equilibrium constant. If $K_P\text{ <<1}$ forward reaction is not spontaneous. The backward reaction is favorable. If $K_P\text{ >>1}$ forward reaction is spontaneous.