Metals, Non-Metals and Metalloids
In 1868, gold-rush prospectors pulled over 3,000 kg of gold nuggets from creeks near Bathurst, NSW — a pure metal that conducted electricity, bent without snapping, and shone like nothing else they'd ever touched.
Printable Worksheets
Print or save as PDF — or build a custom worksheet from any module's questions.
Q1 · List three objects in your kitchen or classroom that you think are made of metal. What clues told you so?
Q2 · A pencil "lead" is actually carbon. Why doesn't it feel or behave like the copper wire next to it, even though both are elements?
● Know
- The four main properties of metals (shiny, malleable, ductile, conductive)
- The properties of non-metals (dull, brittle, poor conductors)
- Where the staircase line sits on the periodic table
● Understand
- Why metalloids sit in between metals and non-metals
- Why metal properties make them useful for wires, tools and structures
- Why silicon's "in-between" nature makes it perfect for computer chips
● Can do
- Classify a sample as metal, non-metal or metalloid from its properties
- Match elements (Fe, Cu, Au, S, O, C, Si, Ge, As) to their categories
- Use the staircase line to predict an element's category
- Malleable
- Ductile
- Brittle
- Conductor
- Metalloid
- Lets heat or electricity flow through easily
- Can be hammered into thin sheets
- In-between element on the staircase line
- Can be pulled into a wire
- Snaps or shatters when struck
Twist a copper wire around a pencil — it bends without snapping. Touch it to both terminals of a battery — current flows through it. Tap it with a hammer — it flattens rather than shattering. These observations tell you it's a metal. About three-quarters of all elements are metals, sitting on the left of the periodic table staircase, and sharing this famous set of four properties.
| Property | What it means | Everyday example |
|---|---|---|
| Shiny (lustrous) | A freshly cut metal surface reflects light. | A 50-cent coin, polished aluminium. |
| Malleable | Can be hammered into sheets without breaking. | Aluminium foil pressed paper-thin. |
| Ductile | Can be drawn into long thin wires. | Copper wire inside an extension cord. |
| Good conductor | Lets heat and electricity flow through. | A saucepan base (heat); copper wires (electricity). |
Common metal examples to remember:
- Iron (Fe) — used for steel beams, train rails, car bodies.
- Copper (Cu) — used for electrical wires and water pipes.
- Gold (Au) — used in jewellery and inside computer chips because it doesn't tarnish.
Most metals are also solid at room temperature. The famous exception is mercury (Hg), a liquid metal once used in thermometers.
Metals are , can be hammered into sheets (), pulled into wires () and let electricity flow through them (good ).
Non-metals sit on the right of the staircase line. They are almost the opposite of metals.
| Property | What it looks like |
|---|---|
| Dull | No metallic shine. Sulfur is a dull yellow powder. |
| Brittle | Solids shatter when hit. A piece of sulfur or carbon snaps like chalk. |
| Poor conductor | Heat and electricity do not flow through. (Exception: graphite, a form of carbon, does conduct electricity.) |
| Many are gases | Oxygen, nitrogen, hydrogen, chlorine — at room temperature they are gases. |
Common non-metal examples to remember:
- Sulfur (S) — bright yellow powder used to make matches and rubber.
- Oxygen (O) — the gas in the air that keeps you alive.
- Carbon (C) — the element in pencil leads, charcoal and diamonds.
Right on the staircase line sit a small group of elements called metalloids. They show some metal properties and some non-metal properties — they sit between the two camps.
- Silicon (Si) — looks shiny like a metal but shatters like glass. Used in computer chips and solar panels.
- Germanium (Ge) — used in old transistors and modern fibre-optic cables.
- Arsenic (As) — toxic; was once used in green paints and rat poison.
The most useful metalloid is silicon. It conducts electricity — but only sometimes, and only when scientists "dope" it with tiny amounts of other elements. That switchable conducting is exactly what makes a semiconductor. Every smartphone, laptop and solar panel relies on silicon's in-between behaviour.
Wrong: "Anything shiny must be a metal." Galena (a non-metal compound of lead and sulfur) has a metallic shine but is brittle and a poor conductor. Looks alone aren't enough.
Right: Use multiple properties together — shiny AND malleable AND ductile AND a good conductor — before calling something a metal.
Wrong: "All metals are solid." Mercury is a metal that is liquid at room temperature, and gallium melts in your hand.
Right: Most metals are solid at room temperature, but a few (mercury, gallium, caesium) melt easily. The properties of being shiny and conducting still apply.
Wrong: "Carbon is a metal because graphite conducts electricity." Graphite is a special form of carbon — but carbon itself is a non-metal (dull, brittle, mostly insulating).
Right: Carbon is a non-metal. Graphite is an unusual exception that conducts electricity, but carbon still fails the other metal tests.
Engineers and designers choose materials based on these property categories. A quick tour:
| Job | Element chosen | Why |
|---|---|---|
| Electrical wire | Copper (metal) | Very ductile and a great conductor. |
| Aircraft body | Aluminium (metal) | Light, malleable, doesn't rust quickly. |
| Plastic wire coating | Carbon-based plastic (non-metal) | Poor conductor — stops electricity escaping. |
| Computer chip | Silicon (metalloid) | Semi-conducts electricity — switchable. |
| Gold jewellery | Gold (metal) | Doesn't tarnish; easy to shape. |
So the classification isn't just trivia — it tells you what each element can do for us.
A friend hands you a shiny grey sample that looks like polished metal. You drop it on the bench and it shatters like glass. You touch a battery to it — it conducts electricity only weakly. Predict: is it a metal, a non-metal, or a metalloid? Explain in one sentence, then reveal.
How close was your prediction?
Nice — you spotted that combining shiny + brittle + weak conductor pins down a metalloid.
Good — being surprised is the point. Using one property alone (like shine) is misleading.
At the start of this lesson you were asked: Silicon is shiny like a metal but smashes like glass when you hit it — where does it fit? Did you have a guess for this one?
Now you know about metals, non-metals and metalloids, write a proper answer. Explain where silicon fits and use at least three specific properties to back up your answer.
Q1. List the four main properties of a metal and give one everyday example for each property. (3 marks)
Q2. Classify each element as a metal, non-metal or metalloid, and give one reason for your classification: copper (Cu), oxygen (O), silicon (Si), gold (Au). (4 marks)
Q3. A student says "Anything shiny that conducts electricity must be a metal." Evaluate this claim. Use at least one specific example (e.g. silicon, graphite, galena) to support your answer. (4 marks)
Answers
▾MCQ 1
A — Metals are shiny, malleable, ductile and good conductors. B describes non-metals; C and D are mixed.
MCQ 2
C — Dull and brittle are classic non-metal properties. Sulfur is a yellow non-metal.
MCQ 3
D — Metalloids sit right on the staircase line that separates metals (left) from non-metals (right).
MCQ 4
B — Silicon is a metalloid. Its switchable conductivity (semiconductor behaviour) is exactly what computer chips need.
MCQ 5
C — Iron is a metal. Sulfur and oxygen are non-metals; silicon is a metalloid.
Short Answer 1
Model answer: (1) Shiny / lustrous — a freshly polished 50-cent coin reflects light. (2) Malleable — aluminium foil hammered into thin sheets. (3) Ductile — copper drawn out into a long thin wire inside an extension cord. (4) Good conductor — a saucepan base conducts heat to cook food, copper wires conduct electricity.
Short Answer 2
Model answer: Copper (Cu) = metal (shiny, ductile, excellent conductor — used in wires). Oxygen (O) = non-metal (a gas at room temperature, does not conduct electricity). Silicon (Si) = metalloid (shiny like metal but brittle; semi-conducts electricity — used in computer chips). Gold (Au) = metal (shiny, malleable, good conductor, used in jewellery and electronics).
Short Answer 3
Model answer: The claim is partly correct because most metals are shiny and conduct electricity, so shine + conducting often points to a metal. However, the claim is not complete: graphite (a form of carbon) is dark-shiny and conducts electricity but is still a non-metal because it is brittle and most other forms of carbon don't conduct. Galena (a lead-sulfur compound) is metallic-looking but brittle and a poor conductor — it isn't even an element. So we need more than two properties — malleability, ductility, full conductivity and position on the periodic table — to call something a metal.