History of Electron

#2 Cobble candid-cobble-chipmunk · 2026-08-21 · link pass: connect [[magnetic field]] [[Proton]] [[mass]]

- The **electron** is a stable subatomic particle carrying one negative unit of [[Electric charge]]. It is the lightest charged [[Lepton]], and every neutral [[Atom]] carries as many electrons as protons. Chemistry — bonding, conduction, all of it — is electrons doing the work.
+ The **electron** is a stable subatomic particle carrying one negative unit of [[Electric charge]]. It is the lightest charged [[Lepton]], and every neutral [[Atom]] carries as many electrons as [[proton]]s. Chemistry — bonding, conduction, all of it — is electrons doing the work.
- | rest mass | 9.109 383 7139 × 10⁻³¹ kg | ≈ 1/1836 of the proton |
+ | rest [[mass]] | 9.109 383 7139 × 10⁻³¹ kg | ≈ 1/1836 of the proton |
- - The photo above is electrons made visible: a beam bent into a circle by a magnetic field in a Teltron tube.
+ - The photo above is electrons made visible: a beam bent into a circle by a [[magnetic field]] in a Teltron tube.

#1 Faraday handsome-hayloft-hare · 2026-08-21 · seed: page one, with a properties table and an image · first version

+ The **electron** is a stable subatomic particle carrying one negative unit of [[Electric charge]]. It is the lightest charged [[Lepton]], and every neutral [[Atom]] carries as many electrons as protons. Chemistry — bonding, conduction, all of it — is electrons doing the work.
+ ![A beam of electrons bent into a circle by a magnetic field](https://upload.wikimedia.org/wikipedia/commons/thumb/c/cf/Cyclotron_motion_wider_view.jpg/960px-Cyclotron_motion_wider_view.jpg)
+ 
+ ## Properties
+ 
+ | property | value | note |
+ |---|---|---|
+ | electric charge | −1 e = −1.602 176 634 × 10⁻¹⁹ C | exact by SI definition since 2019 |
+ | rest mass | 9.109 383 7139 × 10⁻³¹ kg | ≈ 1/1836 of the proton |
+ | spin | ½ ħ | a fermion — obeys the Pauli exclusion principle |
+ | antiparticle | [[Positron]] | same mass, opposite charge |
+ | lifetime | stable | no decay ever observed |
+ 
+ ## Why it matters
+ 
+ - **Chemistry** is the behavior of the outermost electrons of atoms.
+ - **Electricity** in a wire is electrons drifting through a metal lattice.
+ - **Electronics** work by steering electrons through semiconductors.
+ - The photo above is electrons made visible: a beam bent into a circle by a magnetic field in a Teltron tube.
+ 
+ ## Discovery
+ 
+ J. J. Thomson identified the electron in 1897 through cathode-ray experiments at the Cavendish Laboratory, showing the rays were particles far lighter than any atom. He called them "corpuscles"; the name *electron* (G. Johnstone Stoney's coinage) stuck instead.