Ch.13 - Chemical KineticsSee 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

Chemical Kinetics is the study of reaction rates, which is the speed in which reactants are consumed to make products. 

Chemical Reactions & Kinetics

Concept #1: Understanding Chemical Kinetics. 

The word “kinetics” is derived from the Greek word “kinesis”, which means motion. So Chemical Kinetics deals with the speed of motion experienced by reactants as they are allowed to react. 

Concept #2: Kinetics in a Chemical Reaction. 

A chemical reaction is simply reactants breaking down and reassembling to form products. 

Factors Influencing Reaction Rates

Depending on certain conditions, a chemical reaction can either happen very quickly in seconds or take place over several years. 

Concept #3: Slow vs. Fast Reactions. 

Concept #4: Kinetics & the Concentration of Compounds. 

In order for a chemical reaction to occur two molecules must collide. The more concentrated a solution then the greater the chance of them colliding. 

Concept #5: Kinetics & the Surface Area of Compounds. 

For a collision between molecules to be successful, molecules join at their active sites. The larger their surface area then the more places the molecules can successful join. 

Concept #6: Kinetics & Temperature. 

The General Rule is increasing the reaction temperature by 10oC will cause the rate to double. 

Concept #7: Kinetics & the Catalyst. 

A catalyst helps to speed up the rate of a reaction by lowering the energy of activation (Ea).

Additional Problems
A factor that decreases the activation energy for a reaction: I)          decreases the rate constant II)        increases the rate constant III)       has no effect on the rate constant IV)       makes the product yield increase V)        might be a catalyst        A) II and IV       B) I, IV, and V       C) I and IV       D) II and V       E) IV and III
Which of the following has no effect on the rate of a reaction?       A) concentrations of reactants B) value of ΔH° C) activation energy D) temperature of reactants E) presence of a catalyst
The value for the rate constant of a reaction can generally be expected to (A) decrease with increasing temeprature. (B) increase with increasing temperature. (C) decrease with increasing temeprature only when reaction is exothermic. (D) increase with increasing temeprature only when the reaction is exothermic.
This chapter dealing with Chemical Kinetics has many formulas and here we organize them into their major sections. 
Which of the following is not temperature dependent? 1. rate 2. k rate constant 3. t1/2, half-life 4. Ea, activation energy
The oxidation of propane is given by the reaction below: C3H8 (g) + O2 (g) → 3 CO2 (g) + 4 H2O (l) Which graph accurately shows the concentration of CO2 as a function of the time for the reaction above?
Which of the following would result in a decrease in the rate for the following reaction? N2 (g) + O2 (g) ⇌ 2 NO (g) a) Changing the temperature. b) Adding a catalyst c) Increasing the volume by adding solvent. d) Adding N2 (g).
An increase in the temperature of the reactants causes an increase in the rate of reaction. The best explanation for this behavior is that as the temperature increases: A. the concentration of reactants increases B the activation energy decreases.  C. the collision frequency increases.  D. the fraction of collisions with total kinetic energy > E a increases.  E. the activation energy increases. 
Which one of the following changes would alter the rate constant (k) for the reaction: 2A + B → products? A. increasing the concentration of A B. increasing the concentration of B C. increasing the temperature D. measuring k again after the reaction has run for a while 
Which is true for every reaction if the temperature is raised? a) chemical reactions favor products b) chemical reactions favor reactants c) no change is observed d) equilibrium constants increase e) none of these
All of these changes increase the value of the rate constant for a reaction   except (A) decreasing the activation energy. (B) raising the temperature. (C) adding a catalyst. (D) increasing the concentration of reactants.
A chemist burns steel wool in air and observes that it burns slowly. She burns steel wool in pure oxygen and observes that it burst into flames, burning more rapidly. Which factor is affecting this reaction rate?A. The physical state of the reactants.B. The reaction temperature.C. The reactant concentrations.D. The presence of a catalyst.
Which of the following will lead to a DECREASE in the rate of an elementary chemical reaction? (Choose one answer.)(a) Increase the temperature.(b) Increase the concentration of a reactant.(c) Increase the concentration of a product.(d) Change the structure of the reactants so the reaction has a higher activation energy. (e) All of the above
Which of the following will lead to a DECREASE in the rate of an elementary chemical reaction? (Choose one answer.) (a) Decrease  the temperature. (b) Increase concentration of a reactant(c) Decrease the concentration of a product(d) Change the structure of the reactants so the reaction has a lower activation energy.(e) All of the above
Given that the chemical reaction: S 8 (g) + 2 O2 (g) → 4 S2O (g) is found to have a rate law of: Rate = k [S8]. How many of the following actions would increase the rate of this reaction: Lowering temperature; Increasing conc. of O2; Increasing conc. of S8; Adding a catalystA. None of themB. OneC. TwoD. ThreeE. All of them
Which of the following statements is true regarding a chemical reaction where the reactants and products are separated by an energy barrier?A.The rate constant for the reaction will increase with temperature.B.The rate constant for the reaction will increase as the activation energy decreases.C.The rate constant for the reaction will decrease with an increase in temperature.D.The rate constant for the reaction will decrease as the activation energy decreases. 1. D only2. B only3. A only4. A and B
How would the following events affect the rate of the following general reaction?
How do enzymatic catalysts increase the rates of reactions?  a. they shift the reaction equilibrium toward the products. b. they promote the formation of a transition state. c. they lower the activation energy of the reaction.  d. they increase the concentration of reactants. e. they decrease the free energy of the reaction.
Which of the following would cause the rate of a chemical reaction to slow? a. Increase the temperature of the reactants b. Increase the volume that the reactants take up c. Increase the surface area of the reactants d. Increase the concentration of the reactants
Be sure to answer all parts.Just as the depletion of stratospheric ozone threatens life on Earth today, its accumulation was one of the crucial processes that allowed life to develop in prehistoric times: 3O2 (g) → 2O3 (g) At a given instant, the reaction rate in terms of [O2] is 2.17 x 10-5 mol/L•s. What is it in terms of [O3]? Enter your answer in scientific notation. 
The rate of the following reaction is 0.780 M/s. What is the relative rate of change of each species in the reaction? A + 4B → 2C Δ[A]/Δt = Δ[B]/Δt = Δ[C]/Δt = 
The rate of the following reaction is 0.480 M/s. What is the relative rat of change of each species in the reaction? A + 3B → 2C Δ[A]/Δt = Δ[B]/Δt = Δ[C]/Δt =
Glucose (C6H12O6) is combusted according to the following equation: C6H12O6 (s) + 6O2 (g) → 6CO2 (g) + 6H2O (g) When glucose is being consumed at a rate of 0.12 moles per second, what is the rate of production of carbon dioxide? A) 0.02 mol/s B) 0.12 mol/s C) 0.24 mol/s D) 0.60 mol/s E) 0.72 mol/s
Consider the reaction, 2D(g) + 3 E(g) + F(g) → 2 G(g) + H(g) When H is increasing at 0.47 mol/Ls, how quickly is G increasing? Give your answer to 3 decimal places. 
If the rate of change of Cl2 is-0.0350M/s, what is the rate of change of NO? 2NO (g) + Cl2 (g) → 2NOCl (g) 
The gas NO reacts with H2, forming N2 and H2O: 2NO (g) + 2H2 (g) → 2H2O (g) + N2 (g) If Δ[NO]/Δt = -19.0 M/s under a given set of conditions, what are the rates of change of [N2] and [H2O]? Rate of change of [N2]: Rate of change of [H2O]:
If the rate of change of Cl2 is -0.0575 M/s, what is the rate of change of NO? 2 NO (g) + Cl (g) → 2NOCl (g)
Consider the reaction 8H2S(g) + 4O2(g) → 8H2O(g) + S8(g) Δ[H2S]/Δt = -0.030 M/s A. Find Δ[O2]/Δt. B. Find Δ[H2O]/Δt. C. Find Δ[S8]/Δt.D. Find the rate of the reaction. 
Consider the following reaction: 4NO2(g) + O2(g) → 2N2O5(g) The rate of this reaction can be expressed as
What is the overall reaction order for CO in a reaction with the following rate law? Rate = K[Cl2][H+]2[CO]2a. Secondb. Fourthc. Firstd. Fifthe. Third 
Select the factors that might influence the rate of a chemical reaction. a. changing the temperature b. changing the concentration of reactants c. adding a catalyst d. reaction rate cannot change
a. If Δ[NO_3]/Δt is -21.51 x 104 mM/min in the following reaction, what is the rate of appearance of NO2? NO3(g) + NO(g) → 2NO2(g) Δ[NO2]/Δt = b. What is the rate of change in [NO2] in the following reaction if delta [NO3]/Δ t is -23.22 x 10-1 mM/min? 2NO3(g) → 2 NO2(g) + O(g) Δ[NO2]/rΔ =