All Chemistry is a reference site: a periodic table with the measured properties of every element, a page for each of them, and tools that run in the browser.
It has been going since 2013. It is nobody's course and it certifies nobody — it is a place to look something up, check it, or work out what is going on.
What is here
The periodic table. All 118 elements with their measured values: atomic mass, electron configuration, electronegativity, radius, ionisation energy, electron affinity, oxidation states, melting and boiling points, density, year of discovery. Each element has its own page, and the table can be recoloured by category, state, block or electronegativity.
Tools. A structural formula editor for drawing a molecule or writing out a reaction, with nothing to install.
How the element pages are arranged
The properties are split into two blocks, and that is not a decision about layout. A property of the atom holds wherever that atom is — in a crystal, in a molecule, in a star. A property of the simple substance describes a lump of material at a stated temperature and pressure, and says nothing about the atom on its own.
Oxygen the element has an electron configuration. Oxygen the substance boils at 90 K — and ozone, built from exactly the same atoms, boils somewhere else entirely. Running the two together in one table is how people come to believe that "oxygen is a gas" is a fact about the element.
Where the data comes from
The measured values are from the PubChem periodic table (US National Institutes of Health, public domain), and the names from Wikidata (CC0). An element's position in the table is calculated from its atomic number rather than taken from a source: the layout is fixed, and 118 rows are easier to check by eye than a query.
Get in touch
Use the contact form. Corrections to the data are especially welcome — if something does not match your own reference book, tell us and we will look into it.