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Chemistry History

Today in chemistry history: J. J. Thomson and the discovery of the electron

On this day (30 April) in 1897, Joseph J Thomson announced the discovery of the electron. It was the first time a subatomic particle had been discovered. This graphic takes a quick look at his discovery; for a more detailed explanation, check out this Institute of Physics article. For more on different models of the atom […]

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Chemistry History General Chemistry

The History of the Atom – Theories and Models

All matter is made up of atoms. This is something we now take as a given, and one of the things you learn right back at the beginning of high school or secondary school chemistry classes. Despite this, our ideas about what an atom is are surprisingly recent: as little as one hundred years ago, scientists […]

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General Chemistry

Mole Day – Avogadro & The Mole

Today, 23rd October, is Mole Day – which might put you in mind of small, furry, burrowing animals. However, they don’t even seem to have a commemorative day of any kind; we’re actually talking about the mole in chemistry, a quantity that essentially allows us to ‘count’ atoms and molecules in a more convenient way. […]