12.1 -12.2 Flashcards
What does collision theory state?
-An effective reaction requires sufficient energy and the correct position of the entities
What is activation energy?
The minimum energy that entities must reach before they can react
What does it mean if a large quantity of energy is needed to start a reaction?
The reaction will proceed slowly
When is energy needed?
To break bonds
When is energy released?
When bonds are formed
What is bond energy?
The energy required to break a chemical bond and the energy released when a bond is formed
When is a reaction endothermic?
When the energy needed to break the bonds is greater than the energy released when new bonds are created
When is a reaction exothermic?
When the energy created when bonds are created is greater than the energy needed to break original bonds
What is a catalyst?
A substance that increases the rate of a chemical reaction without being consumed in the overall process
What does a catalyst do?
Reduces the quantity of energy required to start a reaction and results in catalyzed reaction producing a greater yield producing a greater yield in the same period of time
What is a common example of a catalyst in vehicles?
Platinum catalytic converter in exhaust system that increase the rate of combustion
What is an enzyme?
A compound that acts as a catalyst in a living system
How do catalysts work?
They accelerate a reaction by providing an alternative lower energy pathway from reactants to products
What are intermediates?
Chemical entities that form with varying stability at the end of each step in a reaction mechanism
