Metals vs non-metals
metalShiny element that is a good conductor of electricity and heat, and which forms basic oxides. are placed on the left-hand side of the periodic table, and non-metalElement that is a poor conductor of electricity and heat, and which forms acidic oxides. on the right.
Learn more on metallic bonding in this podcast.
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Physical properties
The table summarises some typical physical propertiesA description of the appearance of a substance or how it acts without involving chemical reactions. For example, state, melting point, conductivity, etc. of metals and non-metals.
| Metals | Non-metals |
| Shiny | Dull |
| High melting points | Low boiling points |
| Good conductors of electricity | Poor conductors of electricity |
| Good conductors of heat | Poor conductors of heat |
| High density | Low density |
| Malleable | Brittle |
| Metals | Shiny |
|---|---|
| Non-metals | Dull |
| Metals | High melting points |
|---|---|
| Non-metals | Low boiling points |
| Metals | Good conductors of electricity |
|---|---|
| Non-metals | Poor conductors of electricity |
| Metals | Good conductors of heat |
|---|---|
| Non-metals | Poor conductors of heat |
| Metals | High density |
|---|---|
| Non-metals | Low density |
| Metals | Malleable |
|---|---|
| Non-metals | Brittle |
Some elementA substance made of one type of atom only. have properties that are not typical. For example:
- mercury (a metal) has a low melting pointThe temperature at which a solid changes into a liquid as it is heated. and exists as a liquid at room temperature
- graphite, a form of carbon (a non-metal), has a high boiling pointThe temperature at which a substance rapidly changes from a liquid to a gas. and is also a good conductorAn electrical conductor is a material which allows an electrical current to pass through it easily. It has a low resistance. of electricity
A substance with a high densityA measure of compactness and the ratio of mass to volume. It is usually measured in kilograms per metre cubed (kg/m3) or grams per centimetre cubed (g/cm3). means it has a high mass for its size.
malleableCapable of being hammered or pressed into a new shape without being likely to break or return to the original shape. substances can be bent or hammered into shape without shattering, while brittleIf something is brittle it is easily broken. substances shatter when bent or hit.
ductileA ductile material is capable of being drawn into thin sheets or wires without breaking. means that a substance can be drawn out into a long wire without snapping or breaking.
Chemical properties
The reactions of elements are related to the electron arrangementThe order electrons are arranged into between different energy levels. of their atoms (and so to their atomic numberThe number of protons in the nucleus of an atom. Also called the proton number.). Electrons in the outer shells are lost, gained or shared in reactions. Elements in a group have similar chemical properties because they have the same number of electrons in their outer shells.
| Reaction | Electrons in outer shells | Type of bonding formed |
| metal + non-metal | Lost from metal atoms, gained by non-metal atoms | Ionic |
| non-metal + non-metal | Pairs of electrons shared | Covalent |
| Reaction | metal + non-metal |
|---|---|
| Electrons in outer shells | Lost from metal atoms, gained by non-metal atoms |
| Type of bonding formed | Ionic |
| Reaction | non-metal + non-metal |
|---|---|
| Electrons in outer shells | Pairs of electrons shared |
| Type of bonding formed | Covalent |
In general:
- metals form positively charged ionElectrically charged particle, formed when an atom or molecule gains or loses electrons. but non-metals form negatively charged ions
- metals form basicBases react with acids to make salts, and form alkaline solutions if they dissolve in water. Substances or solutions that act as bases are said to be basic. oxides, some of which dissolve to form alkalineHaving a pH greater than 7. solutions, but non-metals form acidicHaving a pH lower than 7. oxides