Atoms and Elements
Map
Arrows point from what you learn first to what it opens. Point at a concept to light up its chain and where it comes back deeper. Right-click a concept (or press and hold it) for its lessons and stories.
- Proven to depth123
- Open
- Locked
- Comes back deeper
Learning path
In the order the concepts build on each other.
- AtomLockedThe tiny pieces all matter is made of, far too small to see: a human hair is about a million atoms wide. Most tiny particles of a substance are small groups of atoms held together.Opens after: Particle model
- Parts of an atomLockedAn atom has a tiny, heavy centre, the nucleus, made of protons (plus charge) and neutrons (no charge), with very light electrons (minus charge) moving around it like a cloud. Almost all of an atom's mass is in its nucleus.Opens after: Atom
- ElementLockedA substance made of only one kind of atom, like gold, iron or oxygen. The number of protons decides which element an atom belongs to; about 118 are known, and about 90 are found in nature.Opens after: Parts of an atom
- Chemical symbolLockedThe short name of an element: one capital letter, or a capital and a small letter, like O for oxygen and Cl for chlorine. Some come from Latin, like Fe for iron and Au for gold, and chemists everywhere use the same ones.Opens after: Element
- Periodic tableLockedA chart of all the elements in order of atomic number (the number of protons), with rows cut so that elements that behave alike sit in the same column. Dmitri Mendeleev drew the first one in 1869.Opens after: Chemical symbol
- Metals and non-metalsLockedMost elements are metals: shiny, bendy, and good carriers of heat and electricity. The non-metals sit on the right of the periodic table; many are gases, and the solid ones are usually dull and crumbly. Only a few metals, like iron, stick to a magnet.Opens after: Periodic table, Properties of materials
Connections to other domains
- Element leads to MoleculeChemical Bonding
- Atom needs Particle modelMatter and Its Properties
- Metals and non-metals needs Properties of materialsMatter and Its Properties
- Chemical symbol leads to Chemical formulaChemical Bonding