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: The following reaction in aqueous solution was found to be first order in [OH- ], first order In [C2H5Br], and inverse first order In Br - . C2H5Br + OH - → C2H5OH + Br - Which one of the following mechanisms Is consistent with the observed reaction order? A.) C2H5Br ⇌ C2H5 + + Br - fast  C2H5 + + OH - → C2H5OH slow B.) C2H5Br + H2O → C2H5OH + H+ + Br - slow H+ + OH - → H2O fast C.) C2H5Br ⇌ C2H5 + + Br - slow C2H5 + + OH - → C2H5OH fast D.) C2H5Br ⇌  C2H5 + + Br - slow OH - + Br - → HOBr fast HOBr + C2H5+ → C2H5OH + Br - fast 

Problem

The following reaction in aqueous solution was found to be first order in [OH- ], first order In [C2H5Br], and inverse first order In Br - .

C2H5Br + OH - → C2H5OH + Br -

Which one of the following mechanisms Is consistent with the observed reaction order?

A.) C2H5Br ⇌ C2H5 + + Br - fast 

C2H5 + + OH - → C2H5OH slow

B.) C2H5Br + H2O → C2H5OH + H+ + Br - slow

H+ + OH - → H2O fast

C.) C2H5Br ⇌ C2H5 + + Br - slow

C2H5 + + OH - → C2H5OH fast

D.) C2H5Br ⇌  C2H5 + + Br - slow

OH - + Br - → HOBr fast

HOBr + C2H5+ → C2H5OH + Br - fast