"The plum pudding model is one of several historical scientific models of the atom. First proposed by J. J. Thomson in 1904..."
Proposed by J.J. Thomson in 1904, it proposed that the atom was a positively charged sphere with negatively charged electrons embedded in it, like raisins in a plum pudding.
The structure of an atom: The basic structure of an atom, including its three main components: protons, neutrons, and electrons.
Atomic theory: The history and development of atomic theory, including the ideas of Democritus, John Dalton, and Ernest Rutherford.
Cathode rays: The rays produced in a vacuum tube by a stream of electrons, which led to Thomson's discovery of the electron.
J.J. Thomson: The life and career of J.J. Thomson, including his research on cathode rays and his development of the Plum Pudding Model.
The Plum Pudding Model: Thomson's model of the atom, which proposed that electrons were embedded in a positively charged "pudding" of matter.
Atomic spectra: The specific patterns of light emitted or absorbed by an atom, which provided evidence for the existence of discrete energy levels.
Isotopes: Atoms of an element that have the same number of protons but different numbers of neutrons, which led to the development of the concept of atomic mass.
X-rays: High-energy electromagnetic waves that were discovered by Rutherford and used to study the structure of atoms.
Radioactive decay: The process by which unstable atoms undergo spontaneous nuclear decay, which led to the development of the concept of atomic half-life.
Atomic models: The various models of the atom that have been proposed over time, including the Bohr Model, wave mechanics, and quantum mechanics.
Modern atomic theory: The current understanding of the structure and behavior of atoms, including the role of subatomic particles, energy levels, and quantum mechanics.
Applications of atomic theory: The many applications of atomic theory in fields such as chemistry, physics, and engineering, including the development of nuclear energy, radiation therapy, and nanotechnology.
"The model tried to explain two properties of atoms then known: that electrons are negatively charged particles and that atoms have no net electric charge."
"First proposed by J. J. Thomson in 1904 soon after the discovery of the electron, but before the discovery of the atomic nucleus..."
"The plum pudding model has electrons surrounded by a volume of positive charge, like negatively charged 'plums' embedded in a positively charged 'pudding'."
"First proposed by J. J. Thomson in 1904 soon after the discovery of the electron..."
"...atoms have no net electric charge."
"...like negatively charged 'plums' embedded in a positively charged 'pudding'."
"The plum pudding model is one of several historical scientific models of the atom."
"...soon after the discovery of the electron..."
"...but before the discovery of the atomic nucleus..."
"The plum pudding model has electrons surrounded by a volume of positive charge..."
"First proposed by J. J. Thomson in 1904..."
"The model tried to explain two properties of atoms then known: that electrons are negatively charged particles and that atoms have no net electric charge."
"...a volume of positive charge..."
"...like negatively charged 'plums'..."
"...embedded in a positively charged 'pudding'."
"...the discovery of the electron..."
"The plum pudding model has electrons surrounded by a volume of positive charge..."
"...in 1904 soon after the discovery of the electron..."
"The plum pudding model is one of several historical scientific models of the atom."