Discovered cathode rays had the following properties: travel in straight lines from the cathode; cause glass to fluoresce ; impart a negative charge to objects they strike ; are deflected by electric fields and magnets to suggest a negative charge ; cause pinwheels in their path to spin indicating they have mass .
Using a Cathode ray tube, he observed that nearby chemicals glowed. Further experiments found very penetrating rays coming from the CRT that were not deflected by a magnetic field. He named them X-RAYS.
Discovered that inert gases had a stable electron configuration which lead to their chemical inactivity.
Pioneer of valence Theory. Because of his research he proposed that the difference of the maximum positive and negative valence of an element tends to be eight. This has become to be called ABEGG’S RULE .
Einstein showed that if light consisted of particle-like quantised photons, where the energy of the photon depended upon its wavelength, the photoelectric effect could be explained. This work led to a revolution in the understanding of both the electron and light. Light could behave as both a wave and a particle, depending upon the experiment.
Linus Pauling used empirical heat of reaction data to introduce the elemental property of electronegativity which he defined as: " The desire of an atom to attract electrons to itself ".
Introduced ELECTRONEGATIVITY which defined the new atomic property as: " The power of an atom in a molecule to attract electrons to itself .“
H A N S H E L L M A N & R I C H A R D F E Y N M A N
The Hellmann-Feynman theorem states that once the spatial distribution of electrons has been determined by solving the Schrödinger equation, all the forces in the system can be calculated using classical electrostatics.
L I S E M E I T N E R, O T T O H A H N & S T R A S S M A N
Conducted experiments verifying that heavy elements capture neutrons and form unstable products which undergo fission. This process ejects more neutrons continuing the fission chain reaction.