Chapter 16: Reaction Rates

Question 1

Collision Theory

Answer 1

1. Reactions occur when particles collide
2. Effective collisions that cause reactions must have sufficient energy & proper orientation
3. Collisions usually occur 2 particles at a time

Question 2

Reaction Mechanism

Answer 2

Series of small steps that, added together, compose a complex process

Question 3

Factors That Affect Reaction Rates

Answer 3

1. Concentration of reactants (As the concentration of reactants increases, so does the likelihood that reactant molecules will collide)
2. Temperature (At higher temperatures, reactant molecules have more kinetic energy, move faster, and collide more often and with greater energy)
3. Surface Area (Larger surface area = more space for collisions = more collisions)
4. Presence of a catalyst or inhibitor (Catalysts speed up reactions by changing the mechanism of the reaction; Inhibitors are chemicals that prevent a reaction from happening)

Question 4

Catalysts

Answer 4

Catalysts increase the rate of a reaction by decreasing the activation energy of the reaction; not consumed in reaction

Question 5

Elementary Reaction

Answer 5

One step of a larger reaction

Question 6

Rate-Determining Step

Answer 6

Slowest step which determines the overall rate of the reaction

Question 7

Reaction Mechanism Diagram

Answer 7

Intermediate product: created during reaction, used up before end
Catalyst: first appears as reactant, later appears as products; makes intermediate spike smaller