Chapter 13, Problem 55E

Interpretation Introduction

(a)

Interpretation:

To calculate $\text{ΔrG°}$ for the following reaction.

${\text{H}}_{\text{2}}{\text{(g)+I}}_{\text{2}}\text{(g)}\stackrel{}{\rightleftharpoons }\text{2HI(g)}$

Concept introduction:

The Gibb’s equation of thermodynamic purposed a relation between $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ with temperature. The mathematical expression of Gibb’s equation can be written as:

$\text{ΔG = ΔH - TΔS }$

With the help of this equation, one can predict the change in $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$. ${\text{K}}_{\text{p}}$ or $\text{Kc}$ are the equilibrium constants for the reaction which are ratio of gaseous and aqueous products and reactant molecules.

$\text{A + B }\rightleftharpoons \text{C + D }$

$\text{K = Kp = }\frac{\text{[PC] [PD]}}{\text{[PA] [PB]}}$

Here, ‘a’ represents the active mass and ‘P’ represents the partial pressure.

The relation between equilibrium constant and $\Delta \text{rG}°$ can be written as:

$\text{ΔrG° = - 2}\text{.303 RT log K}$

Here,

• R = 8.314 J / mol .K
• T = temperature in Kelvin

Interpretation Introduction

(b)

Interpretation:

To calculate $\text{ΔrG°}$ for the following reaction.

${\text{N}}_{\text{2}}\text{O(g)+}\frac{\text{1}}{\text{2}}{\text{O}}_{\text{2}}\underset{}{\rightleftharpoons }\text{2NO(g)}$

Concept introduction:

The Gibb’s equation of thermodynamic purposed a relation between $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ with temperature. The mathematical expression of Gibb’s equation can be written as:

$\text{ΔG = ΔH - TΔS }$

With the help of this equation, one can predict the change in $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$. ${\text{K}}_{\text{p}}$ or $\text{Kc}$ are the equilibrium constants for the reaction which are ratio of gaseous and aqueous products and reactant molecules.

$\text{A + B }\rightleftharpoons \text{C + D }$

$\text{K = Kp = }\frac{\text{[PC] [PD]}}{\text{[PA] [PB]}}$

Here, ‘a’ represents the active mass and ‘P’ represents the partial pressure.

The relation between equilibrium constant and $\Delta \text{rG}°$ can be written as:

$\text{ΔrG° = - 2}\text{.303 RT log K}$

Here,

• R = 8.314 J / mol .K
• T = temperature in Kelvin

Interpretation Introduction

(c)

Interpretation:

To calculate $\text{ΔrG°}$ for the following reaction.

${\text{N}}_{\text{2}}{\text{O}}_{\text{4}}\text{(g)}\stackrel{}{\rightleftharpoons }{\text{2NO}}_{\text{2}}\text{(g)}$

Concept introduction:

The Gibb’s equation of thermodynamic purposed a relation between $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ with temperature. The mathematical expression of Gibb’s equation can be written as:

$\text{ΔG = ΔH - TΔS }$

With the help of this equation, one can predict the change in $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$. ${\text{K}}_{\text{p}}$ or $\text{Kc}$ are the equilibrium constants for the reaction which are ratio of gaseous and aqueous products and reactant molecules.

$\text{A + B }\rightleftharpoons \text{C + D }$

$\text{K = Kp = }\frac{\text{[PC] [PD]}}{\text{[PA] [PB]}}$

Here, ‘a’ represents the active mass and ‘P’ represents the partial pressure.

The relation between equilibrium constant and $\Delta \text{rG}°$ can be written as:

$\text{ΔrG° = - 2}\text{.303 RT log K}$

Here,

• R = 8.314 J / mol .K
• T = temperature in Kelvin

Interpretation Introduction

(d)

Interpretation:

To calculate $\text{ΔrG°}$ for the following reaction.

${\text{2Fe}}^{\text{3+}}{\text{(aq)+Hg}}_{\text{2}}^{\text{2+}}\text{(aq)}\stackrel{}{\rightleftharpoons }{\text{2Fe}}^{\text{2+}}{\text{(aq)+2Hg}}^{\text{2+}}\text{(aq)}$

Concept introduction:

The Gibb’s equation of thermodynamic purposed a relation between $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$ with temperature. The mathematical expression of Gibb’s equation can be written as:

$\text{ΔG = ΔH - TΔS }$

With the help of this equation, one can predict the change in $\text{ΔS}$, $\text{ΔH}$ and $\text{ΔG}$. ${\text{K}}_{\text{p}}$ or $\text{Kc}$ are the equilibrium constants for the reaction which are ratio of gaseous and aqueous products and reactant molecules.

$\text{A + B }\rightleftharpoons \text{C + D }$

$\text{K = Kp = }\frac{\text{[PC] [PD]}}{\text{[PA] [PB]}}$

Here, ‘a’ represents the active mass and ‘P’ represents the partial pressure.

The relation between equilibrium constant and $\Delta \text{rG}°$ can be written as:

$\text{ΔrG° = - 2}\text{.303 RT log K}$

Here,

• R = 8.314 J / mol .K
• T = temperature in Kelvin