AQA · GCSE · Combined Science
Course version: 8464 · Version from Sept 2018
In pure metals, atoms are arranged in layers, which allows metals to be…
Full specification wording
Properties of metals and alloys: In pure metals, atoms are arranged in layers, which allows metals to be bent and shaped. Pure metals are too soft for many uses and so are mixed with other metals to make alloys which are harder.
Pure metals contain atoms of one element only, packed in regular layers.
Checked against the AQA 8464 specification (opens in a new tab) on .
- Point 2 of 3
- 2 key terms
Study notes
From the checked teaching notes for this specification point.
The idea
Pure metals contain atoms of one element only, packed in regular layers. Because all atoms are the same size, a layer can slide over the one below when a force is applied, so the metal bends or is shaped rather than cracking. This explains malleability and ductility. However, the same easy sliding makes pure metals soft, so they wear or dent in demanding uses. Mixing a pure metal with other metals produces an alloy: the different-sized atoms disrupt the regular layers, so layers no longer slide easily and the alloy is harder.
For example: Pure iron is soft, but adding carbon and other elements makes steel, used for tools, bridges and car bodies.
What earns the marks
- Pure metals contain atoms of a single element arranged in regular layers.
- Layers of identical atoms can slide over one another when a force is applied, so the metal can be bent and shaped.
- Pure metals are too soft for many uses because the layers slide too easily.
- An alloy is a mixture of a metal with other elements, often other metals.
- In an alloy, atoms of different sizes disrupt the regular layers, so the layers cannot slide as easily.
- Disrupted sliding makes the alloy harder than the pure metal.
- A named example, such as steel from iron with carbon, can illustrate the idea.
Common mistakes and how to put them right
Saying that atoms in a pure metal are randomly arranged.
Put it right by stating that pure metal atoms form regular layers.
Claiming that alloy atoms are larger than metal atoms in every case.
Put it right by saying the added atoms are different in size, which may be larger or smaller.
Stating that alloys are harder because they contain stronger bonds.
Put it right by explaining that different-sized atoms distort the layers and prevent them sliding.
Exam tips
- Use the phrase 'layers of atoms slide over each other' when explaining bending or shaping of a pure metal.
- When comparing hardness, link the alloy's different-sized atoms directly to the disruption of the layers.
- Include one named alloy and its use, such as steel for tools or bridges, to support your explanation.
Try the lesson
The start of the Properties of metals and alloys: In pure metals, atoms are arranged in layers, which allows metals to be bent and shaped. Pure metals are too soft for many uses and so are mixed with other metals to make alloys which are harder. lesson, made from checked teaching notes for this specification point.
Have a go first
Which statement describes the arrangement of atoms in a pure metal?
Listen
Pure metals contain atoms of one element only, packed in regular layers. Because all atoms are the same size, a layer can slide over the one below when a force is applied, so the metal bends or is shaped rather than cracking. This explains malleability and ductility. However, the same easy sliding makes pure metals soft, so they wear or dent in demanding uses. Mixing a pure metal with other metals produces an alloy: the different-sized atoms disrupt the regular layers, so layers no longer slide easily and the alloy is harder. For example, pure iron is soft, but adding carbon and other elements makes steel, used for tools, bridges and car bodies. A strong answer earns marks for these points. Pure metals contain atoms of a single element arranged in regular layers. Layers of identical atoms can slide over one another when a force is applied, so the metal can be bent and shaped. Pure metals are too soft for many uses because the layers slide too easily. An alloy is a mixture of a metal with other elements, often other metals. A common slip: Saying that atoms in a pure metal are randomly arranged. Instead, stating that pure metal atoms form regular layers. Exam tip: Use the phrase 'layers of atoms slide over each other' when explaining bending or shaping of a pure metal.
Key words
Say what each word means before you turn the card.
Pure metals
Try answering aloud or in your head before turning the card.
Alloys
Try answering aloud or in your head before turning the card.
See every definition
- Pure metals
- Metals whose atoms are arranged in layers, which allows them to be bent and shaped, but which are too soft for many uses.
- Alloys
- Made by mixing pure metals with other metals, these are harder than the pure metals.
There is more to this lesson
The full lesson goes on to check your understanding and help you earn the marks. Create a free account to carry on, with your progress saved.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge
Test your understanding of Properties of metals and alloys: In pure metals, atoms are arranged in layers, which allows metals to be bent and shaped. Pure metals are too soft for many uses and so are mixed with other metals to make alloys which are harder.
Active recall beats re-reading. Take an instant quiz now to test what you’ve learned and lock it into long-term memory.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge