Metals and Non-Metals

Splitting the elements in two

If you sorted all the elements into just two big piles, the most useful split would be metals and non-metals. Around three-quarters of all elements are metals, and the rest are non-metals (plus a few in-between elements called metalloids). This single divide explains a huge amount about the materials in your home, from the copper in a wire to the carbon in a pencil.

The two groups behave very differently, and the differences come down to a set of properties — features you can test and compare.

What metals are like

Most metals share a recognisable bundle of properties:

• Shiny (lustrous). A freshly cut or polished metal reflects light, like gold, silver and steel.
• Good conductors. Metals let heat and electricity pass through them easily. That is why pans are metal and wires are made of copper.
• Malleable. They can be hammered or rolled into new shapes without shattering — think of a sheet of foil.
• Ductile. They can be stretched into thin wires.
• Strong and dense. Many are tough and feel heavy for their size.
• Sonorous. They make a ringing sound when struck, like a bell.
• Usually solid at room temperature (mercury is the famous liquid exception).

Examples include iron, copper, aluminium, gold, sodium and zinc. Metals sit on the left and middle of the periodic table, which you can explore in The Periodic Table for Beginners.

What non-metals are like

Non-metals are almost the mirror image:

• Dull, not shiny (with exceptions like diamond, a form of carbon).
• Poor conductors of heat and electricity — they are insulators. Graphite, a form of carbon, is an unusual non-metal that does conduct.
• Brittle when solid: they snap or crumble rather than bend, like a stick of charcoal.
• Low density, often light.
• Many are gases at room temperature, such as oxygen, nitrogen and chlorine.

Examples include oxygen, carbon, nitrogen, sulfur and helium. Non-metals cluster in the upper-right part of the periodic table.

A side-by-side comparison

Property	Most metals	Most non-metals
Appearance	Shiny	Dull
Conducts electricity	Yes	No (except graphite)
Hammered into shape	Yes (malleable)	No (brittle)
State at room temp	Mostly solid	Many are gases
Sound when hit	Rings	Dull thud

Keep in mind these are general trends, not strict rules — that is why mercury (a liquid metal) and graphite (a conducting non-metal) are interesting exceptions worth remembering.

The border: metalloids

Right along the zig-zag staircase line that divides the table sit a few elements called metalloids, such as silicon, boron and germanium. They have a mix of properties — for instance, silicon is shiny like a metal but brittle like a non-metal, and it conducts electricity only a little. This "in-between" behaviour is exactly why silicon is the heart of computer chips: a controllable, part-time conductor called a semiconductor.

Why the difference matters in real life

The metal/non-metal split is one of the most practical ideas in chemistry. Engineers choose metals when they need strength and conductivity — bridges, train tracks, wiring, saucepans, coins. They choose non-metals when they need insulation or lightness — the plastic coating on a wire, the rubber of a tyre, the oxygen we breathe. Understanding the link between an element's properties and its job connects to Materials and Their Properties, where the same thinking is used to pick the right stuff for each task.

Try this — a safe conductivity test

With a grown-up, you can compare conductors and insulators using a simple battery, a small bulb in a holder, and two wires (a basic circuit kit). Leave a gap in the circuit and touch different objects across the gap: a metal spoon, a metal key, a coin, then a plastic ruler, a wooden pencil and a rubber band. The bulb lights only when a metal completes the circuit, because metals conduct electricity and the non-metals do not. Only ever use a single small battery — never mains electricity — and ask an adult to set it up.

Once you can spot metals and non-metals, you will understand why everyday objects are built from exactly the elements they are.