3.2Catalysts at Work

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3.2 Catalysts at Work

• 3.2.1. Catalytic Converters

LO I understand how catalytic converters work.
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Catalytic converters in car exhausts

• Contain platinum, palladium and rhodium.

• Convert harmful gases into less harmful ones.

For example


2NO
2NO2
2N2
3O2

2CO
O2
2CO2
The polluting molecules stick to the surface of
the catalyst.
This is called adsorption.
LO I understand how catalytic converters work.
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Unleaded petrol must be used.

• Lead sticks to the surface of the catalyst and
  stops the polluting molecules from adsorbing.

This is known as poisoning the catalyst.
LO I understand how catalytic converters work.
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3.2.2. Heterogeneous Catalysis
LO I understand what is meant by heterogeneous
catalysis.
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In heterogeneous catalysis, the catalyst is in a
. state to the reactants.
different
Ostwald process
Ammonia oxygen
Platinum
Nitric acid
Haber process
Nitrogen and hydrogen
Iron
Ammonia
Vegetable oil and hydrogen
Hydrogenation
Nickel
Margarine
Contact process
Sulphur dioxide and oxygen
Vanadium pentoxide
Sulphuric acid

• In some reactions the by-products
  the catalyst.

poison
The catalyst must be .
regenerated
LO I understand what is meant by heterogeneous
catalysis.
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3.2.3. Homogeneous Catalysis
LO I understand what is meant by homogeneous
catalysis.
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In homogeneous catalysis, the catalyst is in the
. state to the reactants.
same
glucose fructose
confectionary
yeast
grape juice
wine
yoghurt
bacteria
brewing
grain sugars
biological

• Enzymes are catalysts that
  speed up certain reactions by homogeneous
  catalysis

LO I understand what is meant by homogeneous
catalysis.