OBJECTIVES
 describe
the concept of catalyst
 present
catalyst as an effective means of
affecting the reaction rate
 realize
the importance of catalyst and how it
affects your life.
CATALYST
WHAT IS A CATALYST?
the
increase in the rate of a
chemical reaction by lowering its
activation energy due to the
participation of a substance called
CATALYST.
When
this catalyst added to
reaction it increase the rate of
reaction by providing an alternate
reaction pathway with a lower
energy (Ea).
In
Biochemistry they are called
ENZYMES.
2 TYPES OF CATALYSTS
1.ORGANIC-known as enzymes and their role
is to catalyze and regulate specific
reactions in living organisms.
2.INORGANIC-are often metallic compounds
with a high surface energy. This high
surface energy assists in the breaking of
chemical bonds present in the reactant
molecules.
THE EFFECT OF A CATALYST ON
RATE OF REACTION
explains how adding a catalyst affects
the rate of reaction. It assumes
familiarity with basic concepts in the
collision theory of reaction rates, and
with
the
Maxwell-Boltzmann
distribution.
MAXWELL-BOLTZMANN
DISTRIBUTION
describes the distribution of speeds among the
particles in a sample of gas at a given temperature.
The distribution is often represented graphically,
with particle speed on the x-axis and relative
number of particles on the y-axis.
ACTIVATION ENERGY
 Is
the minimum amount of energy that is
required to activate atoms or molecules to
a condition in which they can undergo
chemical
transformation
or
physical
transport.
ACTIVATION ENERGY
 Is
the minimum amount of energy that is
required to activate atoms or molecules to
a condition in which they can undergo
chemical
transformation
or
physical
transport.
Guide questions

Based on the diagram given, how does the energy
of the reactants compare with the energy of the
products?

If the energy of the reactant is greater than the
energy of the product, will energy be released or
absorbed by the reaction? Why do you think so?

If the condition were reversed (to that of no 2)
what do you think will happen and why?
The
net amount of energy in the
breaking and forming of bonds
determines if a reaction is exothermic
or endothermic.