Ch. 17 - Chemical ThermodynamicsWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: One of the major sources of NOx compounds in our atmosphere is the reaction between nitrogen and oxygen, for example N2(g) + 2O2(g) → 2NO2(g) This reaction is not favored at normal surface temperatu

Problem

One of the major sources of NOx compounds in our atmosphere is the reaction between nitrogen and oxygen, for example

N2(g) + 2O2(g) → 2NO2(g)

This reaction is not favored at normal surface temperatures, but it does occur within internal combustion engines when air is mixed with the fuel to provide oxygen for the combustion reaction. 

 

a. Before doing any calculations, predict the sign of ΔS°. ___________________.

 Explain your reasoning.

 

b. Now calculate ΔH° and ΔS° for the above reaction. Some thermodynamic data is provided in the table below.

 

c. Is there a temperature range at which the above reaction would be spontaneous? If so, give the temperature range. If not, speculate on why the reaction occurs at higher temperatures.