Periodic Trends Explorer
Colour the periodic table by radius, electronegativity or ionisation energy and see the trends.
Click any element to see its trend across its period and down its group.
About the Periodic Trends Explorer
Free interactive periodic table trends. Colour elements by atomic radius, electronegativity or first ionisation energy, click any element for details, and see the trends across periods and down groups. Built for chemistry, the periodic trends explorer runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
Colour the periodic table by radius, electronegativity or ionisation energy and see the trends. Use it to explore chemistry ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Periodic Trends Explorer
- Use the controls to change Trend arrows. The simulation reacts instantly.
- Pick an option such as Electronegativity, Atomic radius, Ionisation energy, Atomic number to switch modes or load an example.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Colour by electronegativity and find the top-right corner.
- Switch to atomic radius and compare Li and F.
- Click an element to read its numbers.
- Find the alkali metal with the lowest ionisation energy.
Key ideas you can learn
- Atomic radius decreases across a period and increases down a group.
- Electronegativity and ionisation energy increase across a period and decrease down a group.
- Noble gases have very high ionisation energies because their shells are full.
Where this is used in the real world
Chemists use periodic trends to predict bond types, reactivity, and which elements make good conductors, batteries and catalysts.
Who is this simulation for?
Chemistry students from middle school to university, teachers who need a virtual demonstration, and anyone without access to a lab. It is safe, free and repeatable as many times as you like.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
Why does atomic radius get smaller across a period?
The nuclear charge increases while electrons are added to the same shell, so the nucleus pulls the electron cloud in more tightly.
Which element is the most electronegative?
Fluorine, with an electronegativity of 3.98 on the Pauling scale.
Is the Periodic Trends Explorer free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Periodic Trends Explorer work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.