Collision Theory In order for a reaction to occur, reactant particles must collide with each other. In order for a reaction to occur, the collisions must be effective. Effective collisions = sufficient energy and correct orientation. Chemical Kinetics Factors Affecting Reaction Rate
H 2 + I 2 2HI
Factors Affecting Rate of Reaction 1. Nature of Reactants 2. Surface Area 3. Temperature 4. Concentration 5. Pressure 6. Catalyst Increasing frequency of effective collisions increases rate of reaction.
1. Nature of Reactants _____________________________ bonded substances are slower to react than ______________________________ bonded substances.
How does increasing surface area affect reaction rate? Large Piece of Mg Small Pieces of Mg Mg(s) + 2HCl(aq) MgCl 2 (aq) + H 2 (g)
2. Surface Area Draw a curve (graph) showing the relationship between surface area and reaction rate: Relate this relationship to collision theory: Surface Area Reaction Rate As surface area increases, reaction rate ________________.
3. Temperature Draw a curve (graph) showing the relationship between temperature and reaction rate: Relate this relationship to collision theory: Temperature Reaction Rate As temperature increases, reaction rate __________________.
Concentration HC 2 H 3 O 2 + NaHCO 3 NaC 2 H 3 O 2 + H 2 CO 3 Acetic SodiumSodiumCarbonic Acid BicarbonateAcetate Acid H 2 CO 3 H 2 O + CO 2 Carbonic Water Carbon Acid Dioxide
4. Concentration Draw a curve (graph) showing the relationship between concentration and reaction rate: Relate this relationship to collision theory: Concentration Reaction Rate As concentration increases, reaction rate ________________.
5. Pressure Draw a curve (graph) showing the relationship between pressure and reaction rate: Relate this relationship to collision theory: Pressure Reaction Rate As pressure increases, reaction rate ________________.
6. Catalyst Catalyst: The addition of a catalyst ___________ reaction rate. Definition of a catalyst:
Homework Collision Theory: Orange Book: Pg. 110, Q 1-10 *Pg. 121, Q 1, 2, 4, 5 *Pg. 123, Q 18, 19, 21, 22, 23 * Must do. Other HW questions are optional.