1. J.J. Thomson
His model of the atom

2. Covered in this lesson
This lesson explains JJ Thomson's experiments that led to the discovery of the electron.
The discovery of negatively charged electrons smaller than the atom using a cathode ray tube.

3. Cathode Ray Tube
A cathode ray tube is a glass tube with most of the air taken out and metal on both ends.
An electrical current is applied (electron beam)
(diagram wikipedia)

4. Discovery of the Particles, We Call Electrons
J.J. Thomson found the beam was deflected by electric and magnetic fields.
He determined the beam consisted of negatively charged particles smaller than atoms that we now call electrons.
He found electrons in atoms of various metals and suggested they are found in all atoms.

5. J. J. Thomson’s Model
J.J. Thomson’s model of the atom consists of a sphere filled with a positively charged cloud containing negative particles (electrons) spread throughout the cloud.
(diagram wikipedia)