Interactive chemistry

Build matter from particles

Change protons, neutrons, and electrons. Watch the element, isotope mass, charge, and electron shells respond—then explore the first twenty elements and test chemical bonds.

Part 1

Atom builder

The proton count alone decides the element. Neutrons change the isotope; electrons change the ion’s charge.

Protons

Neutrons

Electrons

Mass number: 12
Electron shells: 2–4

CCarbonneutral atom

Part 2

Explore the first twenty elements

Select an element to connect its atomic number, category, mass, and real-world role.

NonmetalNoble gasAlkali metalAlkaline-earth metalMetalloidHalogenPost-transition metal

Choose an element above to inspect it.

Part 3

Check your chemistry model

Use the atom builder, periodic table, and particle stories to solve ten questions instead of guessing.

Question 1

Sodium transfers one electron to chlorine. What kind of bond forms?

Question 2

Two oxygen atoms share electrons. What kind of bond joins them in O₂?

Question 3

Which pair is most likely to form an ionic compound?

Question 4

Which particle count decides an element’s atomic number?

Question 5

A neutral atom has 8 protons. How many electrons does it have?

Question 6

Two carbon atoms have 6 protons but different neutron counts. What are they?

Question 7

Magnesium loses two electrons. What charge does the ion have?

Question 8

Oxygen has 8 electrons. How are they arranged in the first two shells?

Question 9

Hydrogen and oxygen share electrons in a water molecule. Which bond is this?

Question 10