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J. J Thomson and the Electron

Claudia Gold and Mackenzie Donachie

Born in Cheetam hill, Manchester on December 18th, 1856

Enrolled at Owens College in 1870 and entered Trinity College in 1876 as a minor scholar

Eventually became the master of trinity college in 1918

Went to America in 1896 to give four lectures and on his return from America, he conducted an original study of Cathode rays leading to the discovery of the electron

Married Rose Elizabeth (one of his students) in 1890 and had two children

Died on August 30, 1940 at the age of 83.

Biography

He originally started studying Cathode rays in 1894 which glowing beams of light that follow an electrical discharge in a high-volume tube

When J. J. Thomson passed the Cathode rays through the vacuum, he was able to measure the angle at which they deflected which allowed him to calculate the ratio of the electrical charge to the mass of the particles. (c/m ratio)

From this, he discovered that the ratio remained the same no matter what type of gas was used, which led to the conclusion that the particles that made up the gases were universal

Research

{ J.J Thomson discovered that all matter is made up of much smaller particles than atoms.

These particles were originally called “corpuscles” but now known as electrons

Research Cont.

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J.J Thomson’s Plum Pudding model

{ His discovery of the electron led to the theory that the atom was the smallest fundamental unit

Thomson also contributed to the atomic theory in other ways such as the discovery of neon’s two atoms. He proved the existence of isotopes in a stable element- the first use of mass spectrometry.

Contribution to the Atomic Theory

{ Thomson also researched on the nature of

positive rays in 1911, which led to the discovery of Isotopes. He proved that isotopes could be broke by deflecting positive rays in electric and magnetic fields, which was later named mass spectrometry.

When exploring canal rays, Thomson channeled a stream of ionized neon through a magnetic and electrical field

He measured its deflection by using a photographic plate, and saw two patches of light

The two patches suggested two different parabolas of deflection

Concluded that the neon gas was composed of atoms with two different atomic masses (neon-20 and neon-22)

Discovery of Isotopes

He was awarded the Nobel Prize for Physics in 1906 and completed an autobiography in 1936 called “Recollections and Reflections”.

Achievements

"Famous Scientists." Science Blog RSS. N.p., n.d. Web. 07 Nov. 2013.

"J. J. Thomsons Plum-pudding Model." � � � J. J. Thomsons �Plum-pudding Model� � . N.p., n.d. Web. 07 Nov. 2013.

"J.J. Thomson - Biographical." J.J. Thomson - Biographical. N.p., n.d. Web. 07 Nov. 2013.

"J.J. Thomson Biography." Bio.com. A&E Networks Television, n.d. Web. 07 Nov. 2013.

"Joseph John Thomson." Homepage of the Chemical Heritage Foundation. N.p., n.d. Web. 07 Nov. 2013.

Works Cited