2. A property of a substance is a feature or an attribute that
the substance has.
For example:
Iron = very strong
Copper = doesn’t rust
Gold = nice colour!
Properties of Metals
3. Conduction
Metals can conduct both heat and electricity.
This is because all metal atoms have free electrons
(delocalised electrons) which can move from one atom to the
next.
This lets the heat and electricity ‘move’.
e
e
e
e
4. Most elements in the Periodic Table are metals.
Atoms of metal elements bond by METALLIC BONDING.
A metallic structure exists of a giant lattice of positively
charged ions and delocalised (free) outer electrons.
Metallic Bonding & Structure
5. Alloys
To change the properties of metals they can be mixed with
other metals (or carbon).
These are known as ALLOYS.
Examples include:
Steel – iron & carbon (increase strength)
Stainless steel – iron, chromium & nickel (resists rusting)
Solder – lead & tin (melts at low temperature)
6. Reactivity Series
A Reactivity Series is a league table of how easily metals
react – with the most reactive at the top.
Chemists can study many different reactions to work out a
REACTIVITY SERIES
8. Reaction of Metals with Acids
20 cm3
Sulfuric Acid
2 strips of Magnesium
Stopper
Delivery tube
Tub of water
Upside down
test-tube
full of water
How to collect your gas:
Once you have collected your gas, try and identify it.
9. When acids react with metals, they produce
HYDROGEN gas.
Reaction of Metals with Acids
11. Reaction of Metals with Acids
All metals ABOVE COPPER in the Reactivity Series will
react with acid.
Metal + Acid Salt + Hydrogen
Magnesium + Hydrochloric Magnesium + Hydrogen
Acid Chloride
(this is similar to a neutralisation reaction you did in S2)
Separating Salts
12. What is a Salt?
Salts are compounds which are made when acids react.
Have you seen other substances which will
React with an acid?
Acids can react with:
Metals
Alkalis
Metal Carbonates
Metal Oxides
All these reactions will produce a SALT.
13. Naming Salts
When salts are named:
the first part of the name comes from the METAL
the second part from the ACID
Example:
Hydrochloric acid + Sodium = Sodium chloride
14. If the acid is hydrochloric then the salt will be a chloride.
If the acid is sulfuric the salt will be a sulfate.
If the acid is nitric then the salt will be a nitrate.
Naming Salts
Put the information in red, above, into a simple table so
that you will remember it!
What will your
headings be??
15. Reaction of Metals with Oxygen
When metals react with oxygen they make an oxide:
Metal + Oxygen Metal oxide
Magnesium + Oxygen
Aluminium + Oxygen
N5
17. Flame tests
When compounds containing metals are placed in a
flame, they burn with a distinctive colour.
Metal Flame colour
Flame Testing
18. Flame tests
Chemists can use the colour of the flame to tell which
metals are present in the compound.
19. Extracting Metals
Metals exist in the earth’s crust as METAL ORES, the
natural compound which they exist as.
Normally they are found as the oxide (like iron
oxide) but sometimes as carbonates (like copper carbonate).
20. Extracting Metals
Metals are extracted from their ores in different
ways, depending on the REACTIVITY of the metal.
(More reactive metals are harder to separate from
their ores.)
22. Negative
electrode
Positive
electrode
+ +
+
+ -
- - -
When a DC current is turned on (ie turn on the power pack), the
charged particles move towards the electrode with the opposite
charge:
METALS (POSITIVE) NEGATIVE ELECTRODE
NON-METALS (NEGATIVE) POSITIVE ELECTRODE
Electrolysis is the breaking up of compounds using electricity
Solution
Electrolysis
N5
23. Making Electricity
V
Voltmeter
copper
zinc
Lemon juice acts
as an ELECTROLYTE
When pairs of metals are connected together with an
electrolyte (a solution) an electric current will flow.
In chemistry, this is known as a CELL (but you may call it a battery).
24. Cell (or Battery)
V
Metal A Metal B
Electrolyte
(salt solution)
In chemistry, this is known as a CELL (but you may call it a battery)
An ELECTROLYTE is needed to COMPLETE THE CIRCUIT.
25. A Simple Cell
V
Metal A Metal B
Electrolyte
(ionic solution)
A cell must consist of:
2 DIFFERENT METALS
and an ELECTROLYTE
An ELECTROLYTE is a solution containing IONS (charged particles)
26. Electrochemical Series
Different pairs of electrodes (metals) produce different voltages.
Using the different voltages produced, metals can be organised
into a ‘league table’ (similar to the Reactivity Series).
This is known as an ELECTROCHEMICAL SERIES.
27. Electrochemical Series
Reactive metals are more likely to make electrons (electricity).
If you paired aluminium and calcium together – which is going
to make electrons?
28. A Simple Cell
V
Metal A Metal B
Electrolyte
(ionic solution)
Metals vary in their ability to PRODUCE electrons.
If METAL A is better at producing electrons than METAL B,
the electrons will move from A to B.
29. Electrochemical Series
Rules for connecting metals:
• The further apart the metals are in the series, the
higher the voltage produced
Mg + Al create a lower voltage than Mg + Cu
• Electrons ALWAYS flow from a metal HIGHER in the
series to a metal LOWER
Mg down to Al (NOT Al up to Mg)
30. Flow of Charged Particles
V
Magnesium Copper
Electrolyte
(ionic solution)
Electrons flow through
the wire from Mg to Cu
Ions flow between
the electrodes
31. Electrolyte
An electrolyte is a solution, which contains IONS (charged
particles). An electrolyte completes the circuit, and allows
electricity to be produced.
At a high concentration there are many more ions, which lets
more electricity be produced.
32. More Complicated Cells
V
Magnesium Copper
Electrolytes
(solution)
Salt
Bridge
When there are two half cells, an SALT BRIDGE is used to complete
the circuit.
33. Writing Chemical Formula
The CHEMICAL FORMULA tells us the number of ATOMS of EACH
ELEMENT which are in a compound.
This molecule has
8 x carbon atoms
10 x hydrogen atoms
4 x nitrogen atoms
2 x oxygen atoms
34. Tells us:
• type of atoms
• number of atoms
Na Cl :
In a substance
Contains 1 sodium atom, 1 chlorine atom
Li2SO4 : Contains 2 lithium atoms, 1 sulphur atom, 4 oxygen
atoms
Ca(OH)2 : Contains 1 calcium atom, 2 oxygen atoms,
2 hydrogen atoms
For Example:
Writing Chemical Formula
35. There are 3 different ways to work out formulae depending on the
name of the substance.
1. Models / Structures
Calculating Formulae
38. 2. Using Prefixes
These rules can only be used if the substance name has
a prefix in it such as mono, di, tri, etc
A. Nitrogen monoxide
1 nitrogen
Formula = NO
1 oxygen
40. Prefixes
If the name of the compound contains a PREFIX then we
simply write what the name tells us!
Prefix Meaning
Mono one
Di two
Tri three
Tetra four
Penta five
Hexa six
41. Valency Rule
Group
Number
1 2 3 4 5 6 7 0
Valency 1 2 3 4 3 2 1 0
VALENCY tells us HOW MANY ATOMS an element will combine with
The valency of most elements can be determined from their GROUP
This mean that all elements in GROUP 1 have a VALENCY of 1
all elements in GROUP 6 have a VALENCY of 2
42. Reminder: Valency Rule
This rule uses the valency of the elements to work out
how many atoms will combine
Carbon Hydride
Formula = CH4
C H
4 1
1 4
C1 H4
43. Transition Metals
The TRANSITION METALS do not have a fixed Valency.
Their VALENCY is indicated by the ROMAN NUMERAL in their name.
BUT – we still use the VALENCY RULE to get their formula.
Example 1:
Copper (I) oxide & Copper (II) oxide
Example 2:
Iron (II) chloride & Iron (III) chloride
44. Gram Formula Mass
Mass is how much something weighs.
The mass of a compound can be found by adding together the mass
of all the atoms in the compound’s formula.
(The mass of each element is found in the data table!)
46. Electron Arrangement
How many protons and electrons would be in these atoms?
(1) Sodium (6) Aluminium
(2) Oxygen (7) Sulfur
(3) Helium (8) Calcium
(4) Nitrogen (9) Potassium
(5) Chlorine (10) Neon
Extra: Do you know how the electrons are
arranged around the nucleus???
47. Electron Arrangement
Electrons orbit (move around) in specific paths (energy levels) around
the nucleus of the atom.
Each energy level can hold a maximum number of electrons.
Nucleus
1st
Energy Level (holds max 2 electrons)
2nd
Energy Level
(holds max 8 electrons)
3rd
Energy Level
(holds max 8 electrons)
Could you draw the electron arrangements of the atoms from the
previous slide?
48. Ions
Ions are particles where the number of protons and electrons
are not equal.
Ions form when atoms lose or gain electrons (they do this to have
a full outer level, and become stable!)
The number of electrons depends on the VALENCY of the element.
Group
Number
1 2 3 4 5 6 7 0
Valency 1 2 3 4 3 2 1 0
49. Ions
Metals:
Metal atoms ALWAYS LOSE electrons to form POSITIVE
IONS.
eg Sodium
Sodium is in Group 1 and has a VALENCY 1
so loses 1 electron
The charge is written beside the element symbol:
Na+
(a 1+ charge)
50. Ions
Non-Metals:
Non-metal atoms ALWAYS GAIN electrons to form
NEGATIVE IONS.
eg Chlorine
Chlorine is in GROUP 7 and has a VALENCY 1
so gains 1 electron:
Cl-
(a 1- charge)
