Reaction Rates

Chapter 12.1 and 12.4 of A Natural Approach to ChemistryReaction RatesRates of ReactionsHow fast does a reaction occur?

Why Do We Care?Sometimes we need reactions to happen quickly.Sometimes we need to slow reactions down.

Why Do We Care?How do we know if a reaction is going to occur quickly or slowly?Better yet, how can we control the rate of a reaction?

Rate of ReactionRate of Reaction - how fast a reaction occurs

-how quickly the amount of reactants __________

-how quickly the amount of products __________ decreaseincreaseCollision TheoryCollision Theory In order to react, reactant molecules must collide with each other

How does this relate to reaction rates? In order to increase reaction rate, we must increase the number of collisions.

Factors Affecting Reaction Rate1) Temperature hotter temperatures mean: ____________ moleculesmolecular collisions ___________Reaction rate __________fasterincreaseincreases

Factors Affecting Reaction RateLow ConcentrationHigh Concentration

Which of these will have more collisions?Factors Affecting Reaction Rate2) Concentration higher concentration means:_______ reactant moleculesmolecular collisions ___________Reaction rate __________moreincreaseincreasesFactors Affecting Reaction RateLow Surface AreaHigh Surface Area

Which of these will have more collisions?Factors Affecting Reaction Rate3) Surface Area higher surface area means:_______ reactant molecules available for collisionsmolecular collisions ___________Reaction rate __________moreincreaseincreasesFactors Affecting Reaction Rate

Factors Affecting Reaction Rate4) Catalyst molecule that ____________ the reaction rate without getting used up in the reaction itselfHow does it do this?- It lowers the activation energy of the reactionincreases