JJ Thomson
Thomson's Plum Pudding Model:
- a positive charged sphere that has negative charged electrons inside the sphere - the atom is neutral because the atom has the same number of positive and negative charges
What did he conclude?
- cathode rays are made up of electrons - electrons came from the atoms of the negative electrode - all atoms contain electrons
How long did he live?
1865-1940
Year of discovery
1897
What is a cathode ray?
A cathode ray is a tube that has a piece of metal, called an electrode, at each end. Each electrode is connected to a power source (battery)
Where did he live?
Cheetham Hill, United Kingdom
What is he credited with discovering?
He discovered electrons
What did he find?
He found that the path curved away from a negatively charged plate and toward a positively charged plate
What did he predict?
He put the tube into a magnetic field and predicted that the stream would travel in a straight path
What is JJ Thomson known for doing?
He used a cathode ray to prove that Dalton's solid-ball model could be broken into smaller particles
Why did he find this?
Like charges repel each other, and objects with unlike charges attract each other
Were cathode rays used before JJ Thomson's experiments?
Yes, cathode rays were used before JJ Thomson's experiments
