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
Understanding Collision Theory 

A chemical reaction is successful if reactant molecules can combine together to form a new product. 

Concept #1: Collision Theory Intro

Concept #2: Collision Theory

Concept #3: Collision Theory

Additional Problems
The graph shown displays the effect of two different temperatures on the distribution of kinetic energies of molecules in a sample. One temperature is named "Lower T" and is graphed in blue. The other temperature is named "Higher T" and is graphed in red.If there was a third, new temperature that would be graphed in green and would display the effect of a greater, even higher temperature than "Higher T" on the distribution of kinetic energies of molecules in a sample, describe the shape and relative height of this new green curve as it relates to the existing red "Higher T" curve in the graph.
What factors determine whether a collision between two molecules will lead to a chemical reaction?
Explain how a chemical reaction occurs according to the collision model. Explain the meaning of the orientation factor within this model.
According to the collision theory, all collisions do not lead to reaction. Which choice gives both reasons why not all collisions between reactant molecules lead to reaction?1. The total energy of two colliding molecules is less than some minimum amount of energy.2. Molecules cannot react with each other unless a catalyst is present3. Molecules that are improperly oriented during collision will not react.4. Solids cannot react with gases.A. 1 and 2B. 1 and 3C. 1 and 4D. 2 and 3E. 3 and 4 
The rate of a reaction depends ona) collision frequencyb) collision energyc) collision orientationd) none of the abovee) all of the above
Collision theory expains reaction rates based on molecular collisions. Which of the following statement(s) explains why increasing the temperature would increase the rate of a reaction according to Collision Theory.i. Increasing the temperature increases the number of collisions that exceed the activation energyii. Increasing the temperature decreases the activation energyiii. Increasing the temperature increases the percentage of the collisions with the correct orientation.a. i and iib. ii and iiic. i and iiid. i onlye. ii only
Is each of these statements true? If not, explain why.(e) If reactant molecules collide with greater energy than the activation energy, they change into product molecules.
Is each of these statements true? If not, explain why.(h) Activation energy depends on collision frequency.
Consider the following two gas-phase reactions.(a) AA(g) + BB(g) → 2AB(g)(b) AB(g) + CD(g) → AC(g) + BD(g)If the two reactions have identical activation barriers and are carried out under the same conditions, which one would you expect to have the faster rate?
Which of the following two reactions would you expect to have the smaller orientation factor?a. O(g) + N2(g) → NO(g) + N(g)b. NO(g) + Cl2(g) → NOCl(g) + Cl(g)
Heat transfer to and from a reaction flask is often a critical factor in controlling reaction rate. The heat transferred (q) depends on a heat transfer coefficient ( h) for the flask material, the temperature difference (ΔT) across the flask wall, and the commonly “wetted” area (A) of the flask and bath: q = hAΔT. When an exothermic reaction is run at a given T, there is a bath temperature at which the reaction can no longer be controlled, and the reaction “runs away” suddenly. A similar problem is often seen when a reaction is “scaled up” from, say, a half-filled small flask to a half-filled large flask. Explain these behaviors.
The following reaction has an activation energy of zero in the gas phase: CH3 + CH3 → C2H6Would you expect the rate of this reaction to change very much with temperature?
The following reaction has an activation energy of zero in the gas phase: CH3 + CH3 → C2H6Can you think of a reason for why the activation energy is zero?
The following reaction has an activation energy of zero in the gas phase: CH3 + CH3 → C2H6What other types of reactions would you expect to have little or no activation energy?
Consider the following two reactions:O + N2 → NO + N          Ea = 315 kJ/molCl + H2 → HCl + H          Ea = 23 kJ/molCan you suggest why the activation barrier for the first reaction is so much higher than that for the second?
For the reaction A(g) + B(g) ⟶ AB(g), how many unique collisions between A and B are possible if there are four particles of A and three particles of B present in the vessel?
For the reaction A(g) + B(g) ⟶AB(g), how many unique collisions between A and B are possible if 1.01 mol of A(g) and 2.12 mol of B(g) are present in the vessel?
At 25°C, what is the fraction of collisions with energy equal to or greater than an activation energy of 100. kJ/mol?
If the temperature is increased from 25.°C to 50.°C, by what factor does the fraction of collisions with energy equal to or greater than the activation energy change?Reference Problem 16.59. At 25°C, what is the fraction of collisions with energy equal to or greater than an activation energy of 100. kJ/mol?
Use collision theory to determine which single-step reaction has the smallest orientation factor.a) H + H → H2b) I + HI → I2 + Hc) H2 + H2C=CH2 → H3C–CH3d) All of these reactions have the same orientation factor.
In terms of collision theory, to which of the following is the rate of a chemical reaction proportional? (a) the change in free energy per second
In terms of collision theory, to which of the following is the rate of a chemical reaction proportional?(b) the change in temperature per second
In terms of collision theory, to which of the following is the rate of a chemical reaction proportional?(c) the number of collisions per second
In terms of collision theory, to which of the following is the rate of a chemical reaction proportional?(d) the number of product molecules
You may want to reference (Pages 588 - 592) Section 14.5 while completing this problem.Indicate whether each statement is true or false.(a) If you measure the rate constant for a reaction at different temperatures, you can calculate the overall enthalpy change for the reaction.(b) Exothermic reactions are faster than endothermic reactions.(c) If you double the temperature for a reaction, you cut the activation energy in half.
Indicate whether each statement is true or false.(a) If you compare two reactions with similar collision factors, the one with the larger activation energy will be faster.(b) A reaction that has a small rate constant must have a small frequency factor.(c) Increasing the reaction temperature increases the fraction of successful collisions between reactants.
Chemical reactions occur when reactants collide. What are two factors that may prevent a collision from producing a chemical reaction?
When every collision between reactants leads to a reaction, what determines the rate at which the reaction occurs?
How does an increase in temperature affect rate of reaction? Explain this effect in terms of the collision theory of the reaction rate.
According to collision theory and the Arrhenius concept, which of the following statements about gas-phase chemical reactions are TRUE?i. Reaction rates are proportional to collision frequencyii. The number of effective collisions at a given temperature is related to both the kinetic energy and orientation of the reacting molecules or atomsiii. As the temperature increases, the number of species reaching the transition state of the rate-determining step increasesiv. As the temperature increases, the activation energy of a reaction remains constant. (a) (i) and (ii)(b) (ii) and (iii)(c) (i), (ii), and (iii)(d) (ii), (iii), and (iv)(e) All of the statements are correct
____ energy is the minimum amount of energy that colliding molecules must possess in order for a chemical reaction to occur. a) collision b) activation c) bond