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.
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