METAL
Properties of metals
The general physical properties of metals
Other properties include:
Malleable and ductile
Conduct heat
✓ State
✓ Hardness
✓ Valency
✓ Density
Conduct electricity
luster
✓ Melting and Boiling Points
METAL CRYSTALS
explain many of the
general physical
properties of metals?
Chemical Properties of Metals
water
Metals tend to have low ionization
energies, and typically lose electrons .
Alkali metals (IA)
Nonmetal
Metal
Alkaline earth metals (IIA)
acid
Salt(aq)
PERIODIC TABLE
Trends in Metallic
Character
increase strength,
increase corrosion resistance,
or reduce costs
properties superior to pure metals
Making alloys with other metals is one of the commonest ways of changing the properties of metals. Alloys
are formed by mixing the molten metals together thoroughly and then allowing them to cool and form a
solid.
ALLOYS
Many different coins are made from
cupro-nickel alloys
a) The positions of atoms in a pure
metal crystal before a force is
applied.
b) After the force is applied, slippage
has taken place. The layers in a
pure metal can slide over each
other.
c) In an alloy, slippage is prevented
because the atoms of different size
cannot slide over each other.
ALLOYS
REACTIVITY
SERIES
Reactivity series
the metals with:
✓ water or steam
✓ dilute hydrochloric acid
✓ the reduction of their oxides with
carbon
The metals with: water or steam
Metals from calcium upwards
These react vigorously (and even more
vigorously the higher up the series you go)
with cold water to form the metal
hydroxide and hydrogen.
Metals from magnesium to iron
These react with steam to give a metal
oxide and hydrogen. Remember that the
aluminium reaction is much slower than
you would expect because of its stable
oxide coating.
Metals below hydrogen
These don't react with water under any
conditions.
Reactions of metals with air, water and dilute acids
THE EXTRACTION OF METALS
❖ A few metals are so unreactive that they
occur
in
an uncombined
state. These
unreactive metals include copper, gold and
silver.
❖ Most metals are too reactive to exist on
their own in the ground. They exist combined
with other elements as compounds called ores
THE EXTRACTION OF METALS
✓ The moderately reactive metals such as iron,
zinc, tin and lead occur either as oxide or as
sulfide ores.
✓ The sulfide ores can easily be converted to
the oxide by heating in air.
✓ The oxide must then be reduced to give the
metal
Metal displacement reactions
In a displacement reaction, a more reactive metal displaces a less reactive metal from solutions of
salts of the less reactive metal
For example:
Metal displacement reactions
Reactive metals are good reducing agents. The
nature of the reaction taking place between zinc and
copper sulfate can be explored in more detail by
looking at the ionic equation:
Aluminium, the more reactive metal, removes oxygen from the less reactive iron in iron(iii) oxide:
In general, a reactive metal will displace a less reactive metal from its oxide.
Thermal decomposition of metal compounds
QUESTION
1) Write a word equation for the reaction of zinc and dilute hydrochloric acid.
2) Select from this list a metal that will not react with hydrochloric acid to produce
hydrogen: magnesium, iron, copper.
3) Write a word equation for the reaction between magnesium and copper(ii)
sulfate solution.
4) State two observations you would see when a piece of magnesium ribbon is
placed in copper(ii) sulfate solution.
5) Write a balanced chemical equation and an ionic equation for the reaction
between magnesium and copper(ii) sulfate solution
QUESTION
a) 𝐂𝐮 + 𝐙𝐧𝐒𝐎𝟒 →
𝐛) 𝐌𝐠 + 𝐙𝐧𝐒𝐎𝟒 →
𝐜) 𝐌𝐠 + 𝐇𝐂𝐥 →
𝐝) 𝐀𝐠 + 𝐇𝐂𝐥 →
𝐞) 𝐂𝐮 + 𝐀𝐠𝐂𝐥 →
QUESTION
a) Fe + … … … … → FeCl2 + … … … …
b) Fe + Cl2 → … … … …
c) Fe + ………. → FeS
d) ……….. + ……….. → AlCl3
e) …………. + ………… → CaCl2 + CO2 ↑ +H2 O
f) …………. + AgNO3 → Cu(NO3 )2 + …………
g) …………. → Al + …………….
h) Al + NaOH + H2O → ………….. + …………….
i) Fe3O4 + ……………→ Fe + ………………
Questions & answers
Invite questions from the audience