C3.4.1

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C3.4.1 Bells, pipes and wires
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Transition metals

• State the typical physical properties of
  transition metals such as iron and copper high
  melting points, good conductors of heat and
  electricity and high density

• Link the above properties to the uses of these
  metals

• Describe the uses of transition metals and their
  compounds as catalysts

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Transition metals
Know where to find the transition metals in the
periodic table...
the large block between Groups 2 and 3 in the
periodic table
Most metals are placed here, including iron,
titanium, copper and nickel.
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Transition metals
 
e.g. iron and copper
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Transition metals
 
e.g. iron
Strong iron / steel
can support large weights without breaking
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Transition metals
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Transition metals
 
e.g. copper
Malleable
and ductile
can be beaten into thin sheets
Thin copper sheeting protects roofs from the
elements low reactivity
copper ductile (can be drawn into wires) and a
good electrical conductor
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Transition metals
 
e.g. copper
Sonorous
- make a ringing sound when hit
Tubular bells made of a copper alloy brass
(zinc and copper).
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Transition metals
 
e.g. iron
Iron melts at 1538C
High melting points
can function in an environment where the
temperature is high
engine block in a motor-car engine
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Transition metals
 
Good conductors of electricity
copper has the best electrical conductivity of
all metals except for silver
lightning conductor
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Transition metals
 
e.g. copper
Good conductors of heat
copper has the best thermal conductivity of all
metals except for silver
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Transition metals
 
e.g. copper
copper is a malleable metal easily bent without
breaking
insulated copper hot water boiler
Good conductors of heat
copper has the best thermal conductivity of all
metals except for silver
copper is an unreactive metal wont react with
water even when very hot
copper piping carrying hot water
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Transition metals
 
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Transition metals
 
e.g. copper
A brass jug (an alloy of copper and zinc)
Pure copper electroplated on to a leaf
Shiny when polished have a lustre
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Transition metals
 
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Transition metals
Transition metal compounds tend to be coloured
when crystalline or in solution
Co(NO3)2
K2CrO4
K2Cr2O7
NiCl2
CuSO4
KMnO4
The element underlined is the transition metal.
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Transition metals - uses
scandium / steel bike frame
scandium alloy base-ball bat
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Transition metals
Titanium replacement knee joint
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Transition metals
vanadium / steel spanner
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Transition metals
chromium /nickel alloy spark plug
chromium plated screws and bolts
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Transition metals
Manganese batteries
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Transition metals
Cobalt - scanner
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Transition metals
Nickel / steel alloy
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Transition metals
copper
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Transition metals
Transition metals and their compounds as
catalysts
Catalysis is the acceleration (increase in rate)
of a chemical reaction by means of a substance
called a catalyst.
A catalyst is a substance that accelerates a
chemical reaction but is itself not consumed by
the overall reaction
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Transition metals
Transition metals as catalysts
Iron in the Haber Process The Haber Process
combines hydrogen and nitrogen to make ammonia
using an iron catalyst
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Transition metals
Transition metals as catalysts
Nickel in the hydrogenation of CC bonds This
process converts unsaturated vegetable oils into
higher melting saturated fats which are more
'spreadable' with a knife!
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Transition metals
Vanadium(V) oxide in the Contact Process The
Contact Process is a reaction which converts
sulphur dioxide into sulphur trioxide the
initial reaction in the manufacture of sulphuric
acid.
Sulphur dioxide gas is passed together with air
(as a source of oxygen) over a solid vanadium(V)
oxide catalyst.
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Transition metals
Exhaust fumes
Hydrocarbon fuels burnt in a car engine are burnt
inefficiently (less oxygen than is needed to
oxidise the fuel to carbon dioxide and water).
Exhaust fumes contain
hydrocarbons (unburned petrol)
nitrogen oxides (nitrogen in the petrol/air
mixture combines with oxygen).
carbon dioxide and water vapour (efficient
combustion of petrol)
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Transition metals
Exhaust fumes
The dangerous components of exhaust gases can be
made safer by converting them into safer
substances.
This is achieved by passing the exhaust gases
over a catalyst of platinum and palladium.
In a catalytic converter, the catalyst is coated
onto a ceramic honeycomb housed in a package
attached to the exhaust pipe.
The idea is to create a structure that exposes
the maximum surface area.
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Transition metals
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Transition metals
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Transition metals
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Transition metals