Discovery of J.J Thomson
Discovery of J.J Thomson: JJ” Thomson. His full name is Joseph John Thomson. He was born on December 18, 1856, in Cheetham Hill, a district of Manchester, England. He studied engineering at Owens College, which is now part of the University of Manchester. Later he did mathematics at Cambridge.
From a young age, Thomson focuses his studies on the structure of atoms, thus discovering the existence of electrons and isotopes, among many other contributions.
In 1890, J. J. Thomson married Rose Elizabeth Paget, daughter of the doctor Edward George Paget, with whom he had two children: a girl, named Joan Paget Thomson, and a boy, name George Paget Thomson.
Discovery of the Electron
J.J.Thomson is credit with the discovery of the electron, which is the negative charge particle in an atom. He is best known for the Thomson atomic theory.
Many scientists studied the electrical discharge of a cathode ray tube. It was Thomson’s interpretation that was important. He took the deflection of the rays by magnets and charged plates as evidence for “bodies much smaller than atoms“. Thomson calculated that these bodies had a mass-to-mass ratio and estimated the value of the charge.
In 1904, Thomson proposed a model of the atom as a sphere of positive matter with electrons, based on electrostatic forces. Therefore, he not only discovered the electron but determined that it was a fundamental part of an atom.
J.J. Thomson’s Death
He died on August 30, 1940, in Cambridge, Cambridgeshire, England. Thomson is burie in Westminster Abbey near Sir Isaac Newton.
Thomson’s Main Contribution to Science
Discovery of Electrons
In 1897, J.J. Thomson discovered a new particle lighter than hydrogen, which he named “electron”.
Hydrogen is consider the unit of measurement of atomic mass. Until then, atoms were the smallest division of matter. Therefore, Thomson was the first to discover negatively charged corpuscular subatomic particles.
Thomson Atomic Theory
Thomson’s discovery of the electron completely changed the way people looked at atoms. Until the late 19th century, atoms are thought to be small solid spheres. In 1903, Thomson proposed a model of the atom that consisted of positive and negative charges, present in equal amounts so that an atom would be electrically neutral. He proposes the atom is a sphere, but that positive and negative charges are embedding within it.
Modern scientists understand that atoms consist of nuclei of positively charged protons and neutrons with positively charged electrons and neutrons orbiting the nucleus. Nevertheless, Thomson’s model is important because it introduced the notion that an atom consists of charged particles.
Discovery of Isotopes
JJ Thomson discovered that neon ions had different masses. Similarly, Thomson showed that neon has two subtypes of isotopes, neon-20, and neon-22. The isotopes study to this day is atoms of the same element, but have different mass numbers in their nuclei, as they are made up of varying amounts of neutrons at their center.
Some interesting facts about JJ Thomson
- Before Thomson’s discovery of electrons, scientists believed that the atom was the smallest fundamental unit of matter.
- Thomson discovered the natural radioactivity of potassium in 1905.
- In 1906, Thomson demonstrated that the hydrogen atom had only one electron.
- In 1890, Thomson married one of his students, Rose Elizabeth Paget. He had a son and a daughter. In 1937 his son George Paget Thomson received the Nobel Prize in Physics.
- Thomson also investigated the nature of positively charged particles. These experiments led to the development of the mass spectrograph.
- Thomson closely associated with the chemists of the time. His atomic theory helped explain atomic bonding and the structure of molecules.
- Thomson published an important monograph in 1913 urging the use of mass spectrographs in chemical analysis.
- Many consider JJ Thomson to be one of the greatest contributions to science for his role as a teacher.
- One of his most famous students was Ernest Rutherford, who succeeded Thomson as professor of physics.