Define cracking
Term used to describe any reaction in which larger molecules are made into smaller molecules
Why do different fractions in fractional distillation column have different boiling points?
Different Van Der Waals forces
What makes catalyst inactive in cracking column?
Coke (carbon from decomposition of hydrocarbons) forms on catalyst surface
In a catalytic cracker, what rises to the top?
-short chain hydrocarbons with low boiling points
Define catalyst
Substance that speeds up a reaction but remains chemically unchanged
Give basic features of catalysts
- do not undergo permanent chemical change
- may change physically (eg. surface crumbling) but can be regenerated
- only small amounts needed
What is homogenous catalysis?
- when catalyst and reactants are in same physical state
What is heterogenous catalysis?
- when catalyst and reactants are in different physical states
What is a catalyst poison and how does it work?
Substance that stops a catalyst from functioning properly
- poison molecules are adsorbed more strongly than reactant, blocks active site
