11. Activation Energy
For a reaction to begin, the molecules must bump into
each other or collide with enough force.
10
12. Activation Energy
For a reaction to begin, the molecules must bump into
each other or collide with enough force.
The reactants must smash into each other with a certain
amount of energy. If they do not, the reaction will not
occur.
10
13. Activation Energy
For a reaction to begin, the molecules must bump into
each other or collide with enough force.
The reactants must smash into each other with a certain
amount of energy. If they do not, the reaction will not
occur.
This energy is called, activation energy.
10
14. Activation Energy
For a reaction to begin, the molecules must bump into
each other or collide with enough force.
The reactants must smash into each other with a certain
amount of energy. If they do not, the reaction will not
occur.
This energy is called, activation energy.
This is also true for reactions that release energy when
they react. An example is gasoline burning.
10
26. Temperature
Changes Rate
Slow the ripening of fruit by putting them in the
refrigerator.
Meat and fish decompose faster at higher
temperatures, producing toxins that can make you
sick. Keep them chilled helps slow the
decomposition rate.
27. Temperature
Changes Rate
Slow the ripening of fruit by putting them in the
refrigerator.
Meat and fish decompose faster at higher
temperatures, producing toxins that can make you
sick. Keep them chilled helps slow the
decomposition rate.
Bacteria grow faster at higher temperature.
31. Temperature Affects Rate
Most chemical reaction speed up when
temperature increase.
The atoms and molecules are always
moving, and they move faster at higher
temperatures.
32. Temperature Affects Rate
Most chemical reaction speed up when
temperature increase.
The atoms and molecules are always
moving, and they move faster at higher
temperatures.
Faster molecules collide with each other
more often and with greater force, which
may be enough to break the old bond.
This is activation energy.
38. Surface Area Affects Rate
Surface Area = 600 cm2
10 cm That is the
amount of surface
10 cm that would be
10 cm touching the other
reactant.
39. Surface Area Affects Rate
What if we cut out little cubes? 1cm x 1cm
10 cm
10 cm
10 cm
40. Surface Area Affects Rate
What if we cut out little cubes? 1cm x 1cm
10 cm How many cubes
10 cm would we have?
10 cm
41. Surface Area Affects Rate
What if we cut out little cubes? 1cm x 1cm
10 cm How many cubes
10 cm would we have?
10 cm 1000 cubes
42. Surface Area Affects Rate
What if we cut out little cubes? 1cm x 1cm
10 cm How many cubes
10 cm would we have?
10 cm 1000 cubes
What would be
the SA of one of
the cubes?
43. Surface Area Affects Rate
What if we cut out little cubes? 1cm x 1cm
10 cm How many cubes
10 cm would we have?
6cm 2 10 cm 1000 cubes
What would be
the SA of one of
the cubes?
44. Surface Area Affects Rate
What is the total SA of all the cubes?
10 cm
10 cm
10 cm
45. Surface Area Affects Rate
What is the total SA of all the cubes?
10 cm 6cm 2 x 1000 =
10 cm
10 cm
46. Surface Area Affects Rate
What is the total SA of all the cubes?
10 cm 6cm 2 x 1000 =
10 cm
6000 cm2
10 cm
47. Surface Area Affects Rate
What is the total SA of all the cubes?
10 cm 6cm 2 x 1000 =
10 cm
6000 cm2
10 cm
SA of Whole cube = 600 cm2
SA of cut up cube = 6000 cm2
56. A substance that speeds up
a chemical reaction.
Catalyst’s do not appear in a
chemical equation because they
are not changed permanently
or used up.
57. Catalysts
- provide a surface for the
reaction to take place,
or
- reduce the activation energy
needed to start the reaction
62. Catalytic Converter
In vehicles, the exhaust passes through the
catalyst.
Catalysts will speed up the reactions that
change incompletely burned substances that
are harmful, such as carbon monoxide, into
less harmful substances like CO2 and H2O.
63. Catalytic Converter
In vehicles, the exhaust passes through the
catalyst.
Catalysts will speed up the reactions that
change incompletely burned substances that
are harmful, such as carbon monoxide, into
less harmful substances like CO2 and H2O.
This results in cleaner air.
68. Large protein molecules that
speed up reactions needed for
your cells to work properly.
- convert food to fuel
- build bone and muscle tissue
- convert extra energy to fat
- produce other enzymes
69.
70. Other Uses of Enzymes
One example is Proteases - a class of enzymes
that work within cells to break down proteins.
Meat tenderizer is one example of a protease.
Contact lens cleaning solutions also contain
proteases that break down proteins formed by
your eyes that can collect on your lenses and
cloud your view.
71. Finished the
KNP!
So, lets see a
catalyst at work!
