The Periodic Table
The periodic table arranges elements in order of atomic number so that elements with similar properties line up in columns.
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Play with the controls to see the idea in action.
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The periodic table arranges elements in order of atomic number so that elements with similar properties line up in columns.
- Columns are called groups
- Rows are called periods
- Metals are on the left and centre
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is The Periodic Table?
Within Chemistry, which covers atoms, bonding, reactions, the periodic table, organic chemistry and the chemistry of everyday life, this topic explains The Periodic Table. Chemistry links what you can see in the lab to the particles and bonds behind it, so each topic here shows that link in a model.
Check that you can explain The Periodic Table in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding The Periodic Table helps you explain why substances behave as they do, from cleaning products and food to medicines.
The Periodic Table in detail
The periodic table arranges the elements in order of increasing atomic number, with elements of similar properties in the same vertical column, called a group. Mendeleev, who arranged elements by atomic mass and left gaps for undiscovered elements, predicted the properties of elements such as gallium, which strengthened acceptance of his table.
The table divides into metals on the left and centre and non-metals on the right. The position of an element tells you its number of outer electrons, its likely reactivity and the type of ions it forms, making it one of the most useful tools in chemistry.
How the interactive helps you understand The Periodic Table
Click a card to flip it and reveal the answer, then move on to the next one.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of The Periodic Table.
Real-life uses and examples
- Use The Periodic Table to explain what happens in a lab experiment and why.
- Link The Periodic Table to everyday products such as cleaning agents, food and medicines.
- Read a chemical equation or diagram and work out what The Periodic Table shows.
Common mistakes to avoid
- Describing what happens without explaining the particles or bonds involved.
- Mixing up the names of substances or ions when you describe The Periodic Table.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about The Periodic Table
What is The Periodic Table?
The periodic table arranges elements in order of atomic number so that elements with similar properties line up in columns.
What are the most important points about The Periodic Table?
The main points are: Columns are called groups; Rows are called periods; Metals are on the left and centre.
Why is The Periodic Table useful?
Understanding The Periodic Table helps you explain why substances behave as they do, from cleaning products and food to medicines.
How can I practise The Periodic Table?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to The Periodic Table?
Related topics in Chemistry include Group 7: Halogens, Metals and Non-Metals, Metallic Bonding.