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Joseph John Thomson was a British physicist and Nobel Laureate in Physics, credited with the discovery of the electron, the first subatomic particle to be discovered. In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles (now called electrons), which he calculated must have bodies much smaller than atoms and a very large charge-to-mass ratio.

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Joseph John Thomson was a British physicist and Nobel Laureate in Physics, credited with the discovery of the electron, the first subatomic particle to be discovered. In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles (now called electrons), which he calculated must have bodies much smaller than atoms and a very large charge-to-mass ratio.

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Thomson is also credited with finding the first evidence for isotopes of a stable (non-radioactive) element in 1913, as part of his exploration into the composition of canal rays (positive ions). His experiments to determine the nature of positively charged particles, with Francis William Aston, were the first use of mass spectrometry and led to the development of the mass spectrograph.

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Ernest Rutherford was born in  New Zealand-born British physicist who came to be known as the father of nuclear physics.

Born: August 30, 1871
Died: October 19, 1937

Aswell Ernest Rutherford is known for his pioneering studies of radioactivity and the atom. He discovered that there are two types of radiation, alpha and beta particles, coming from uranium

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What was Niels Bohr's most significant achievement? Niels Bohr presented an atom model in which the electron could only occupy specific orbits around the nucleus. The electrons were constrained to particular orbits around the nucleus in this atomic model, which was the first to employ quantum theory.

Niels Henrik David Bohr was a Danish scientist who earned the Nobel Prize in Physics in 1922 for his contributions to atomic structure and quantum theory. Bohr was a philosopher as well as a supporter of scientific study.

Niels Bohr offered a hypothesis for the hydrogen atom in 1913, based on quantum theory, which states that some physical quantities have only discrete values. Electrons circulate around a nucleus in predetermined orbits, and if they leap to a lower-energy orbit, the energy difference is radiated.

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Thomson.

Sir

J. J. Thomson

OM PRS

42nd President of the Royal Society
In office
1915–1920
Preceded by | William Crookes
Succeeded by | Charles Scott Sherrington
Master of Trinity College, Cambridge
In office
1918–1940
Preceded by | Henry Montagu Butler
Succeeded by | George Macaulay Trevelyan
Personal details
Born | Joseph John Thomson
18 December 1856
Cheetham Hill, Manchester, England
Died | 30 August 1940 (aged 83)
Cambridge, England
Citizenship | British
Nationality | English
Children | George Paget Thomson, Joan Paget Thomson
Alma mater | Owens College (now the University of Manchester)
Trinity College, Cambridge (BA)
Signature |

Known for | Plum pudding model
Discovery of electron
Discovery of isotopes
Mass spectrometer invention
Electromagnetic mass
First m/e measurement
Proposed first waveguide
Gibbs–Thomson equation
Thomson scattering
Thomson problem
Coining term 'delta ray'
Coining term 'epsilon radiation'
Thomson (unit)
Awards | Smith's Prize (1880)
Royal Medal (1894)
Hughes Medal (1902)
Nobel Prize in Physics (1906)
Elliott Cresson Medal (1910)
Copley Medal (1914)
Albert Medal (1915)
Franklin Medal (1922)
Faraday Medal (1925)
Dalton Medal (1931)
Scientific career
Fields | Physics
Institutions | Trinity College, Cambridge
Academic advisors | John Strutt (Rayleigh)
Edward John Routh
Notable students | Charles Glover Barkla
Charles T. R. Wilson
Ernest Rutherford
Francis William Aston
John Townsend
J. Robert Oppenheimer
Owen Richardson
William Henry Bragg
H. Stanley Allen
John Zeleny
Daniel Frost Comstock
Max Born
T. H. Laby
Paul Langevin
Balthasar van der Pol
Geoffrey Ingram Taylor
Niels Bohr
George Paget Thomson
Debendra Mohan Bose
Lawrence Bragg External video

The Early Life of J.J. Thomson: Computational Chemistry and Gas Discharge Experiments

Sir Joseph John Thomson OM PRS[1] (18 December 1856 – 30 August 1940) was a British physicist and Nobel Laureate in Physics, credited with the discovery of the electron, the first subatomic particle to be discovered.

In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles (now called electrons), which he calculated must have bodies much smaller than atoms and a very large charge-to-mass ratio.[2] Thomson is also credited with finding the first evidence for isotopes of a stable (non-radioactive) element in 1913, as part of his exploration into the composition of canal rays (positive ions). His experiments to determine the nature of positively charged particles, with Francis William Aston, were the first use of mass spectrometry and led to the development of the mass spectrograph.[2][3]

Thomson was awarded the 1906 Nobel Prize in Physics for his work on the conduction of electricity in gases.[4]

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Sir James Chadwick, CH, FRS was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts.

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Sir James Chadwick, CH, FRS was a British physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts.

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By 1920, physicists knew that most of the mass of the atom was located in a nucleus at its center and that this central core contained protons. In May 1932 James Chadwick announced that the core also contained a new uncharged particle, which he called the neutron. Chadwick was born in1891 in Manchester, England.

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Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research

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Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research

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Chadwick was educated at the University of Manchester, where he worked under Ernest Rutherford and earned a master’s degree in 1913. He then studied under Hans Geiger at the Technische Hochschule, Berlin. When World War I broke out, he was imprisoned in a camp for civilians at Ruhleben. He spent the entire war there but nevertheless was able to accomplish some scientific work.

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Niels Bohr was a danish physicist and philosopher born on the 7th of October, 1885 in København (Copenhagen). Bohr died the 18th of November in 1962 at the age of 77.

In 1922 Niels Bohr won the Nobel Prize in physics for his services in the investigation of  the structure of atoms and of the radiation emanating from them.

Niels Bohr began his work on the Manhattan Project after fleeing to Sweden from Denmark because of the German occupation in 1943.

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John Dalton FRS was an English chemist, physicist and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into colour blindness, sometimes referred to as Daltonism in his honour. Wikipedia

Born: September 6, 1766, Eaglesfield, United Kingdom

Died: July 27, 1844, Manchester, United Kingdom

Known for: Atomic theory, Law of Multiple Proportions, Dalton's Law of Partial Pressures, Daltonism

Award: Royal Medal (1826)

Siblings: Mary Dalton, Jonathan Dalton

Parents: Deborah Greenup, Joseph Dalton

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John Dalton FRS was an English chemist, physicist and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into colour blindness, sometimes referred to as Daltonism in his honour. Wikipedia

Born: September 6, 1766, Eaglesfield, United Kingdom

Died: July 27, 1844, Manchester, United Kingdom

Known for: Atomic theory, Law of Multiple Proportions, Dalton's Law of Partial Pressures, Daltonism

Award: Royal Medal (1826)

Siblings: Mary Dalton, Jonathan Dalton

Parents: Deborah Greenup, Joseph Dalton

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He discovered that negatively charged particles existed within the atom, and he proposed the 'Plum Pudding' model, that the negative electrons were embedded in a field of positive charge

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John Dalton (1766-1844) was an English chemist, physicist, and meteorologist, best known for introducing the atomic theory into chemistry and for his work on human optics.

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this is jj Thompson

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Ernest Rutherford, 1871 - 1937. He was a british physicist. He discovered the nuclear structure of an atom, alpha and beta rays and proposed the laws of radioactive decay. He received the Nobel Prize in Chemistry in 1908. - Lucia Jones

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Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research

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Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research

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Niels Henrik David Bohr was a Danish scientist who earned the Nobel Prize in Physics in 1922 for his contributions to atomic structure and quantum theory. Bohr was a philosopher as well as a supporter of scientific study.

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Who Was John Dalton? During John Dalton's early career, he identified the hereditary nature of red-green color blindness. In 1803 he revealed the concept of Dalton's Law of Partial Pressures. Also in the 1800s, he was the first scientist to explain the behavior of atoms in terms of the measurement of weight

Dalton hypothesized that the law of conservation of mass and the law of definite proportions could be explained using the idea of atoms. He proposed that all matter is made of tiny indivisible particles called atoms, which he imagined as "solid, massy, hard, impenetrable, movable particle(s)"

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Neils Bohr was a danish physicist who contributed to the understanding of atomic structure. in 1920, Bohr developed the Bohr model of the atom, in which he proposed that energy levels of electrons are discrete and that the electrons revolve in stable orbits around the atomic nucleus but can jump from one energy level (or orbit) to another.

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n 1897 Thomson discovered the electron and then went on to propose a model for the structure of the atom. His work also led to the invention of the mass spectrograph. The British physicist Joseph John 

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n 1897 Thomson discovered the electron and then went on to propose a model for the structure of the atom. His work also led to the invention of the mass spectrograph. The British physicist Joseph John 

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By 1920, physicists knew that most of the mass of the atom was located in a nucleus at its center and that this central core contained protons. In May 1932 James Chadwick announced that the core also contained a new uncharged particle, which he called the neutron. Chadwick was born in1891 in Manchester, England.

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Task: Research one scientist that helped develop our understanding of the 'Atom'.

You can use the examples in this slide or choose another.

What did the scientist discovery and in what year?

Later, you will choose a post from any student and provide feedback