Chapter 23, Problem 31P

Interpretation Introduction

(a)

Interpretation:

The balance coupled chemical equation for the coupled reaction of 1,3-bisphosphoglycerate with ADP to form 3-phosphoglycerate and ATP with the help of given reaction equations needs to be determined.

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ATP + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -7}\text{.3 kcal/mol}\mathrm{......}\end{array}$

Concept Introduction:

Born- Haber cycle is used to compute the lattice energy of ionic compounds. Lattice energy can be defined as the energy that is needed to break a compound to its constituent's elements. It can also defineas the energy released during the formation of ionic compounds from its constituent elements. It is based on the Hess law. The Hess law states that the enthalpy change for multistep chemical reaction is the sum of all enthalpy changes. It can be written as;

  $\sum \Delta {\text{H}}_{\text{reaction}}\text{ =}\Delta \text{H1 + }\Delta \text{H2+}\Delta \text{H3}\mathrm{....}$

Answer to Problem 31P

  $\text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP}$

Explanation of Solution

Given:

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ATP + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy = -7}\text{.3 kcal/mol}\end{array}$

To get equation for the coupled reaction of 1,3-bisphosphoglycerate with ADP to form 3-phosphoglycerate and ATP, reverse the equation (2) and add it with (1):

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\stackrel{}{\to }{\text{ ATP + H}}_{\text{2}}\text{O Energy change = + 7}\text{.3 kcal/mol}\mathrm{......}\text{(2)}\\ \text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}\\ \text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP}\mathrm{.....}\text{(3)}\end{array}$

Hence the coupled equation must be:

  $\text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP}$

Interpretation Introduction

(b)

Interpretation:

The energy change for the balance coupled reaction of 1,3-bisphosphoglycerate with ADP to form 3-phosphoglycerate and ATP with the help of given reaction equations needs to be determined.

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ATP + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -7}\text{.3 kcal/mol}\mathrm{......}\text{(2)}\end{array}$

Concept Introduction:

Born- Haber cycle is used to compute the lattice energy of ionic compounds. Lattice energy can be defined as the energy that is needed to break a compound to its constituent's elements. It can also define as the energy released during the formation of ionic compounds from its constituent elements. It is based on the Hess law. The Hess law states that the enthalpy change for multistep chemical reaction is the sum of all enthalpy changes. It can be written as;

  $\sum \Delta {\text{H}}_{\text{reaction}}\text{ =}\Delta \text{H1 + }\Delta \text{H2+}\Delta \text{H3}\mathrm{....}$

Answer to Problem 31P

  $\text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP ; energy change = - 4}\text{.5 kcal/mol }$

Explanation of Solution

Given:

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ATP + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy = -7}\text{.3 kcal/mol}\end{array}$

To get equation for the coupled reaction of 1,3-bisphosphoglycerate with ADP to form 3-phosphoglycerate and ATP, reverse the equation (2) and add it with (1):

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\stackrel{}{\to }{\text{ ATP + H}}_{\text{2}}\text{O Energy change = + 7}\text{.3 kcal/mol}\mathrm{......}\text{(2)}\\ \text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}\\ \text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP }\\ \text{Energy change = + 7}\text{.3 kcal/mol -11}\text{.8 kcal/mol}\\ \text{ Energy change = - 4}\text{.5 kcal/mol }\end{array}$

Interpretation Introduction

(c)

Interpretation:

The use of given coupled reaction for the formation of ATP from ADP needs to be explained.

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ATP + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -7}\text{.3 kcal/mol}\mathrm{......}\text{(2)}\end{array}$

Concept Introduction:

Born- Haber cycle is used to compute the lattice energy of ionic compounds. Lattice energy can be defined as the energy that is needed to break a compound to its constituent's elements. It can also define as the energy released during the formation of ionic compounds from its constituent elements. It is based on the Hess law. The Hess law states that the enthalpy change for multistep chemical reaction is the sum of all enthalpy changes. It can be written as;

  $\sum \Delta {\text{H}}_{\text{reaction}}\text{ =}\Delta \text{H1 + }\Delta \text{H2+}\Delta \text{H3}\mathrm{....}$

Answer to Problem 31P

  $\text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP ; energy change = - 4}\text{.5 kcal/mol }$

The given reaction can be used for the formation of ATP from ADP.

Explanation of Solution

Given:

  $\begin{array}{l}{\text{1,3-bisphosphoglycerate + H}}_{\text{2}}\text{O }\stackrel{}{\to }{\text{ 3-phosphoglycerate + HPO}}_{\text{4}}{}^{\text{2-}}\text{ Energy change = -11}\text{.8 kcal/mol}\mathrm{.....}\text{(1)}\\ {\text{ ADP + HPO}}_{\text{4}}{}^{\text{2-}}\stackrel{}{\to }{\text{ ATP + H}}_{\text{2}}\text{O Energy change = + 7}\text{.3 kcal/mol}\mathrm{......}\text{(2)}\\ \text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}\\ \text{1,3-bisphosphoglycerate + ADP }\stackrel{}{\to }\text{ 3-phosphoglycerate + ATP Energy change = - 4}\text{.5 kcal/mol }\end{array}$

Since the energy change for the formation of ATP from ADP is energetically favored because the energy change is negative here therefore it can be used for the formation of ATP from ADP.