lecture 1 Flashcards
(24 cards)
What are chemical reactions?
Any change in the number, type or arrangement and structure of atoms in a molecule
What is a homogeneous reaction?
It is a reaction that involves only a single phase
What are examples of homogenous reactions?
Natural gas combustion, acid/base neutralization
What are heterogenous reactions?
Chemical reactions that involve multiple phases
What are examples of heterogenous reactions?
metal oxidation, dissolution of solids
Are non-catalytic reactions homogenous or heterogenous?
can be either homogeneous or heterogeneous
Are catalytic reactions homogeneous or heterogeneous?
can be either homogeneous or heterogeneous
What is a catalyst?
A material/substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change or consumption
What phase are catalysts in compared to the reactants or products?
Catalysts can be in the same phase or a different phase from the reactants or products.
Just because it is a catalyst does not mean it is a ____ or in a ___ ___.
solid, separate phase
Why are catalysts so important?
Catalysts account for (a) over 95% of all products by volume and (b) greater than 80% of the added value in the chemical industry
_____ of the world economy depends directly or indirectly on ___.
35%, catalysis
What are two example reactions that involve catalysts?
plastic manufacturing, exhaust emission control
What are chemical reactors?
The devices in which chemical reactions are carries out.
What are homogenous reactors?
Single phase reactors
What are examples of Homogenous Reactors?
Industrial Batch, semi-batch, PFR, CSTR
What are heterogenous Catalytic Reactors?
Reactors with at least two phases present
What are some examples of heterogenous catalytic reactors?
Batch, semi-batch, PBR, and FBR
What does PFR stand for?
plug flow reactor
What does FBR stand for?
Fluidized Bed Reactor
What does PBR stand for?
Packed Bed Reactor
What is an elementary reaction?
Describes an actual physical event on the molecular scale. Each elementary reaction describes one individual step needed to transform some reactants to products
What are global reactions?
They describe the net behavior of the reacting system, but not the individual steps required to get from the reactant to the products
