Ch.6 - Thermochemistry WorksheetSee 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
Sections
Internal Energy
Calorimetry
Hess's Law
Enthalpy of Formation
End of Chapter 6 Problems
Additional Practice
Units of Energy
Endothermic & Exothermic Reactions
Additional Guides
Enthalpy

Solution: (a) How much heat is released when 25.0 g of methane burns in excess O2 to form gaseous CO2 and H2O? (b) Calculate the temperature of the product mixture if the methane and air are both at an initial temperature of 0.0°C. Assume a stoichiometric ratio of methane to oxygen from the air, with air being 21% O2 by volume (c of CO 2 = 57.2 J/mol•K; c of H 2O(g) = 36.0 J/mol•K; c of N 2 = 30.5 J/mol•K).

Problem

(a) How much heat is released when 25.0 g of methane burns in excess O2 to form gaseous CO2 and H2O?

(b) Calculate the temperature of the product mixture if the methane and air are both at an initial temperature of 0.0°C. Assume a stoichiometric ratio of methane to oxygen from the air, with air being 21% O2 by volume (c of CO 2 = 57.2 J/mol•K; c of H 2O(g) = 36.0 J/mol•K; c of N 2 = 30.5 J/mol•K).