Mondo Knows Facts
Atomic theory ran from Democritus to Dalton
An ancient guess about indivisible particles became measurable chemistry Democritus proposed in the fifth century BCE that matter consists of tiny indivisible units he called atomos. John Dalton revived the idea in 1808, using fixed combining weights to argue that each element has its own atoms. His model explained why substances combine in simple whole number ratios. It sits in Mondo's science collection, one of 200 facts that each trace back to the reference below.
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Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.
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Tags: chemistry, atoms, history
Atomic theory ran from Democritus to Dalton: the short answers
- Where does this come from, and can I check it?
- An ancient guess about indivisible particles became measurable chemistry. The figure is taken from American Chemical Society, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a science fact?
- Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
- What else can I read about it?
- The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.