Common questions about Electron

Short answers, pulled from the story.

When did J. J. Thomson discover the electron and what was its mass compared to hydrogen?

J. J. Thomson discovered the electron in 1897 and found it was 1400 times lighter than the lightest known atom, hydrogen. This discovery shattered the prevailing belief that atoms were indivisible, revealing that the universe was built from smaller, lighter components. Before this moment, scientists like William Crookes had observed that cathode rays could turn a paddle wheel, proving they carried momentum, yet they remained a puzzle.

Who coined the name electron and what is the origin of the word?

George Johnstone Stoney coined the name electron in 1891 to describe the basic unit of electrical charge. The term derives from the Greek word for amber, elektron, which gave rise to the modern terms electricity and electric. Benjamin Franklin later simplified the view of electricity to a single fluid, labeling the surplus positive and the deficit negative.

When was the wave-particle duality of the electron confirmed and who discovered it?

The wave-particle duality of the electron was confirmed in 1927 when George Paget Thomson and Clinton Davisson observed interference patterns when electron beams passed through thin foils. Louis de Broglie hypothesized that all matter, including electrons, could be represented as waves in 1924. Erwin Schrödinger then formulated a wave equation that described how electron waves propagated, replacing the idea of fixed orbits with probability clouds called orbitals.

When was the positron discovered and what happens when an electron collides with it?

The positron was discovered in 1932 by Carl Anderson after Paul Dirac predicted its existence in 1930. When an electron collides with a positron, both particles are annihilated, producing gamma ray photons. This interaction explains phenomena like vacuum polarization and the anomalous magnetic dipole moment of the electron.

How are electrons used in modern technology and what is their role in metals?

Electrons are used in modern technology to power cathode-ray tubes, enable computers through transistors, and drive electric motors via magnetic fields. In metals, outermost electrons are delocalized, moving freely like a gas to account for high electrical and thermal conductivity. These properties allow electrons to form electric currents and generate magnetic fields that drive electric motors.

When did electrons form in the Big Bang and how did they survive annihilation?

Electrons formed in the first millisecond of the Big Bang when temperatures exceeded 10 billion kelvins and photons reacted to form pairs of electrons and positrons. After 15 seconds, the universe cooled, and most electron-positron pairs annihilated, releasing gamma radiation. An excess of electrons over positrons survived, matching the excess of protons over antiprotons, resulting in a net charge of zero for the universe.

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