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

Solution: Using data from the following reactions and applying Hess's law, calculate the heat change for the slow reaction of zinc with water: Zn (s) + 2H2O (l) → Zn2+ (aq) + 2OH- (aq) + H2 (g)    ΔH°rxn = ? H+

Problem

Using data from the following reactions and applying Hess's law, calculate the heat change for the slow reaction of zinc with water: 

Zn (s) + 2H2O (l) → Zn2+ (aq) + 2OH- (aq) + H2 (g)    ΔH°rxn = ? 

H+ (aq) + OH- (aq) → H2O (l)     ΔH°rxn, 1 = -56 kJ/mol H2

Zn (s) → Zn2+ (aq)    ΔH°rxn, 2 = -153.9 kJ 

1/2 H2 (g) → H+ (aq)     ΔH°rxn, 3 = 0.0 kJ