Q4 SCI Atomic Structures

the basic building block of chemistry.

stable subatomic particle that has a positive charge equal in magnitude to a unit of electron charge

Who discovered proton in the early 1900's

means first high-energy particle-physics studies in the late 20th century

the main constituent of primary cosmic rays

is nearly massless and is not included in the mass number of an atom.

discovered in 1897 by the English physicist J.J. Thomson (Joseph John Thomson) during investigations of cathode rays.

Some electrons occur in a free state with ions in the form of matter known as

move in an orderly arrangement of orbitals, creating a strong attraction between electrons and nucleus that repels repulsion to prevent them from flying apart.

three dimensional description of the most likely location of an electron around an atom