Ch.13 - Chemical KineticsWorksheetSee 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: Energy profiles for the uncatalyzed and bromide-catalyzed decomposition of H2O2.Where are the intermediates and transition states in this diagram?

Problem

A graph has reaction progress on the x-axis and potential energy on the y-axis. Both axes are unscaled. Both an uncatalyzed and a catalyzed reaction are plotted; both begin with reactants at the same potential energy and lead to products at the same potential energy (lower than the reactants), but their energy profiles vary. For an uncatalyzed reaction, the reactants are 2 H2O2. The curve climbs to a smooth, high peak before leading to the products, which are 2 H2O plus O2. For a catalyzed reaction, the reactants are 2 H2O2 plus 2 Br- plus 2 H+. The curve climbs through two transition states (small peaks with the second higher than the first) before declining to the products (2 H2O plus O2 plus 2 Br- plus 2 H+). Both transition state peaks are lower in the catalyzed reaction than the single peak was in the uncatalyzed reaction.

Energy profiles for the uncatalyzed and bromide-catalyzed decomposition of H2O2.

Where are the intermediates and transition states in this diagram?