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Ch.7 Energy, Rate and EquilibriumWorksheetSee all chapters
All Chapters
Ch.1 Matter and Measurements
Ch.2 Atoms and the Periodic Table
Ch.3 Ionic Compounds
Ch.4 Molecular Compounds
Ch.5 Classification & Balancing of Chemical Reactions
Ch.6 Chemical Reactions & Quantities
Ch.7 Energy, Rate and Equilibrium
Ch.8 Gases, Liquids and Solids
Ch.9 Solutions
Ch.10 Acids and Bases
Ch.11 Nuclear Chemistry
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Nature of Energy
First Law of Thermodynamics
Endothermic & Exothermic Reactions
Bond Energy
Thermochemical Equations
Heat Capacity
Thermal Equilibrium (Simplified)
Hess's Law
Rate of Reaction
Energy Diagrams
Chemical Equilibrium
The Equilibrium Constant
Le Chatelier's Principle
Solubility Product Constant (Ksp)
Spontaneous Reaction
Entropy (Simplified)
Gibbs Free Energy (Simplified)

Hess's Law involves the use of partial reactions in the determination of the overall enthalpy of reaction.

Hess's Law

Concept #1: Rearrangement of Thermochemical Equations

Example #1: If the formation equation for boron trioxide is given as the following: 

What will be the new enthalpy value when it is rearranged? 

Practice: Calculate the ∆Hrxn for the following thermochemical equation: 

When given the following: 

Concept #2: Applying Hess’s Law

Example #2: Calculate the ∆Hrxn for overall reaction:

When given the following set of partial reactions:

Practice: Calculate the ∆Hrxn for 

Given the following set of reactions: 

Practice: Calculate the ∆Hrxn for 

Given the following reactions: