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GCSE level revision notes on metal structure,
properties & uses
5e. Comparing and contrasting the typical physical properties
and chemical properties of metals and non-metals
GCSE level practise exam question QUIZ
Foundation
tier (easier)
m/c QUIZ on structure, properties & chemical bonding
of materials
Higher
tier (harder) m/c QUIZ on structure, properties and chemical bonding of
materials
Contrasting the bonding in metallic and non-metallic
elements and their differing physical properties
non-metals
is covalent,
either producing small gaseous molecules (e.g. hydrogen, H2), liquid (e.g.
bromine Br2), or solid molecules (e.g. sulfur, S8) or
giant covalent structures like carbon Cn for diamond or graphite where n
is a very big number!
Since the bonding is neither metallic (or
ionic), they have
different structures, so, not
surprisingly, the
physical properties of non-metals are usually significantly
different e.g.
-
Excluding boron, carbon and silicon
(strongly bonded giant covalent structures), most non-metals have relatively low melting
points and boiling points - weak intermolecular forces (weak bonding) between the
molecules, rather than strong metallic or ionic bonds.
-
Non-metals are poor
conductors of heat (thermal) energy or electrical energy because the
structure do not contain free moving electrons (graphite is an
exception).
-
Solid non-metals look dull, not sonorous
when struck (don't ring like metals do), they are usually more brittle than
metals, have lower densities as well as being
poor conductors of heat and electricity compared to metals.
-
Metals are usually silvery
and shiny in appearance and good conductors of thermal and electrical
energy because of the mobile electrons.
The
main chemical differences are:
non-metals in the top-right of the
periodic table, tend to gain electrons to form negative ions (anions) with a
full outer shell of electrons.
and
metals at the bottom and left of the
periodic table lose electrons to form positive ions (cations).
Just check this out to the left and right
of the black zig-zag line - though some elements near the zig-zag line can
show mixed characteristics and are described as semi-metals or metalloids.
For metals
see sections
5b.
The chemical bonding in metals
- giant lattice structure
5c.
Explaining the properties of metals using
the metallic bonding model
See
A more fuller discussion on
comparing metals, semi-metals and metals
Some more detailed key
points about comparing metallic and non-metallic elements
Below is a cross‑board GCSE/IGCSE revision guide
comparing the physical and chemical properties of metals and non‑metals,
synthesised from authoritative GCSE chemistry resources.
All factual statements
are grounded in the retrieved sources.
GCSE/IGCSE Revision Notes: Metals versus Non‑Metals
(AQA, Edexcel, OCR Gateway, OCR 21st Century, WJEC, CCEA, CIE IGCSE)
Metals and non‑metals differ because of
their electronic structure,
especially the number of outer‑shell electrons, which
determines how they bond and react.
1.
Where Metals and Non‑Metals Are Found on the Periodic Table
- Metals: left and bottom of the periodic table.
- Non‑metals: right and top.
- A zig‑zag line separates them; elements along it are metalloids
(semi‑metals).
Reason:
- Metals have few outer electrons, so they lose
electrons easily.
- Non‑metals have many outer electrons, so they
gain or share electrons.
2.
Physical Properties: Metals versus Non‑Metals
Summary Table (Exam‑critical)
(All properties below are typical, with known exceptions such as graphite
and mercury.)
| Physical Property |
Metals |
Non‑Metals |
Why? |
| Appearance |
Shiny (metallic lustre) |
Dull |
Metallic bonding gives ordered structure. |
| State at room temp |
Mostly solids (except mercury) |
Many gases, some solids |
Non‑metals often form simple molecules. |
| Melting/boiling points |
High |
Low |
Strong metallic bonds versus weak intermolecular forces. |
| Density |
High |
Low |
Closely packed ions versus loosely packed atoms/molecules. |
| Malleability/ductility |
Malleable, ductile |
Brittle |
Layers of ions can slide in metals. |
| Electrical conductivity |
Good conductors |
Poor (except graphite) |
Delocalised electrons in metals. |
| Thermal conductivity |
Good |
Poor |
Delocalised electrons transfer energy. |
3.
Chemical Properties: Metals versus Non‑Metals
How They Form Ions
- Metals: lose electrons → positive ions
(cations).
- Non‑metals: gain electrons → negative ions
(anions).
Reactions with Oxygen
- Metals → basic metal oxides (e.g.,
MgO).
- Non‑metals → acidic oxides (e.g., CO₂,
SO₂).
Reactions with Water
- Some metals react to form metal hydroxides +
hydrogen (e.g., Na + H₂O → NaOH + H₂).
- Non‑metals generally do not react with
water.
Reactions with Halogens
- Metals form ionic compounds (e.g.,
NaCl).
- Non‑metals form covalent molecules
(e.g., HCl, PCl₅).
Bonding Type
- Metals: metallic bonding.
- Non‑metals: covalent bonding (simple molecules or giant
covalent).
4.
Why These Differences Exist (Exam Theory)
Metals
- Few outer electrons → easier to lose electrons.
- Metallic bonding → delocalised electrons →
conductivity, malleability.
- Strong electrostatic attraction → high melting/boiling points.
Non‑metals
- Many outer electrons → easier to gain/share electrons.
- Covalent bonding → simple molecules → low melting/boiling points.
- No delocalised electrons → poor conductivity.
5.
Metalloids (Semi‑Metals)
Some elements show mixed properties, e.g. silicon,
germanium, arsenic.
They lie along the zig‑zag line shown
below.
6.
Typical GCSE level exam Questions
- Compare physical properties of metals and non‑metals.
- Explain why metals conduct electricity.
- Predict whether an element is a metal or non‑metal from its position.
- Explain why metal oxides are basic and non‑metal oxides are acidic.
- Describe how metals and non‑metals form ions.
7.
Student Exam Tips (Cross‑Board)
1. Always link properties to bonding and structure.
Examiners reward explanations, not lists.
E.g., “Metals conduct electricity
because they have delocalised
electrons.”
2. Don’t confuse melting/boiling points with reactivity.
High melting point ≠ high reactivity.
3. Remember exceptions.
- Graphite (non‑metal) conducts electricity.
- Mercury (metal) is liquid at room temperature.
Examiners love these.
4. Oxides are a common exam trap.
- Metal oxides → basic.
- Non‑metal oxides → acidic.
This appears frequently in AQA, Edexcel, OCR, and CIE papers.
5. Use electron diagrams when explaining ion formation.
8.
Typical Misconceptions (Exam Boards Highlight These)
“All metals are magnetic.”
Only iron, cobalt, nickel.
“All non‑metals are gases.”
Many are solids (e.g., sulfur, carbon).
“Non‑metals cannot conduct electricity.”
Non-metal carbon in the form of graphite is a major exception.
“Metals react by gaining electrons.”
Metals lose electrons → cations.
“Non‑metals form ionic compounds with each other.”
They form covalent molecules.
9.
Concise Summary Table
| Feature |
Metals |
Non‑Metals |
| Outer electrons |
Few e.g. 2.8.1 |
Many e.g. 2.8.7 |
| Ion formed |
Positive (cation) |
Negative (anion) |
| Bonding |
Metallic |
Covalent |
| Conductivity |
Good |
Poor (except graphite) |
| Malleability |
Malleable |
Brittle |
| Oxides |
Basic |
Acidic |
| Reaction with water |
Some react |
Rarely react |
| Reaction with halogens |
Ionic compounds |
Covalent compounds |
What
next?
GCSE level practise exam question QUIZ
Foundation
tier (easier)
m/c QUIZ on structure, properties & chemical bonding
of materials
Higher
tier (harder) m/c QUIZ on structure, properties and chemical bonding of
materials
Recommend next:
Sub-index: Part 5
Metallic Bonding – structure and properties of metals
5a.
Metals and their
position in the Periodic Table of elements
5b.
The chemical bonding in metals
- giant lattice structure
5c.
Explaining the properties of metals using
the metallic bonding model
5d.
Alloys -
improved design and problems using metals e.g.
fatigue and corrosion
Perhaps of interest for further study?
Index for
ALL chemical
bonding and structure notes
Overview of the Periodic Table
(GCSE/IGCSE level)
How can
metals be made more useful? (GCSE/IGCSE/A
level)
Transition Metals Revision Notes
(GCSE/IGCSE level)
3d block Transition Metals Chemistry
(Advanced A Level Notes)
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