Chapter 9, Problem 96AE

(a)

Interpretation Introduction

Interpretation: The standard enthalpy change for nitromethane of the reaction needs to be detremined for the given balance reaction.

  ${\text{CH}}_{\text{3}}{\text{NO}}_{\text{2(l)}}{\text{ + O}}_{\text{2 (g) }}\stackrel{}{\to }{\text{CO}}_{\text{2(g) }}{\text{ + N}}_{\text{2(g) }}{\text{ + H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

Concept Introduction:At constant volume the change in heat for a system to change the internal energy is represented as ΔE or q_V. At constant pressure the change in heat for a system to change the enthalpy is represented as ΔH or q_p.

The $\text{ΔH}$ for a chemical reaction can be calculated with the help of difference between $\text{ΔH}$ of product and reactant.

  $\text{ΔH= }\sum {\text{ΔH}}_{\text{product}}\text{ - }\sum {\text{ΔH}}_{\text{reactant}}$

(b)

Interpretation Introduction

Interpretation: The mass of nitrogen produced when 15.0 L flask containing a sample of nitromethane with ${\text{O}}_{\text{2 (g) }}$ and heated in 100 °C needs to be determined. The total pressure of flask is 950 torr and mole fraction of nitrogen is 0.134 after reaction complete.

  ${\text{CH}}_{\text{3}}{\text{NO}}_{\text{2(l)}}{\text{ + O}}_{\text{2 (g) }}\stackrel{}{\to }{\text{CO}}_{\text{2(g) }}{\text{ + N}}_{\text{2(g) }}{\text{ + H}}_{\text{2}}{\text{O}}_{\text{(g)}}$

Concept Introduction: At constant volume the change in heat for a system to change the internal energy is represented as ΔE or q_V. At constant pressure the change in heat for a system to change the enthalpy is represented as ΔH or q_p.

The $\text{ΔH}$ for a chemical reaction can be calculated with the help of difference between $\text{ΔH}$ of product and reactant.

  $\text{ΔH= }\sum {\text{ΔH}}_{\text{product}}\text{ - }\sum {\text{ΔH}}_{\text{reactant}}$