Ch.6 - Thermochemistry WorksheetSee all chapters
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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
Thermochemical Equation
Hess's Law
Enthalpy of Formation
End of Chapter 6 Problems
Additional Practice
Units of Energy
Additional Guides
Endothermic & Exothermic Reactions
Enthalpy
LearnAdditional Practice
Next SectionCalorimetry

Solution:
A gas-phase reaction was run in an apparatus designed to maintain a constant pressure.
Predict whether w is positive, negative, or zero.

Solution: A gas-phase reaction was run in an apparatus designed to maintain a constant pressure.Predict whether w is positive, negative, or zero.

Problem

A gas-phase reaction was run in an apparatus designed to maintain a constant pressure.

A piston applies pressure to a cylinder containing two O2 molecules and two N2 molecules. This leads to four NO molecules.

Predict whether w is positive, negative, or zero.

Solution

Establish the formula of work and determine the sign of the work for the transformation given

Recall that work can be calculated as:

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Practice Problems
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