

Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
History of the Atom proposed by John Dalton, J. J. Thompson, Lord Ernest Rutherford, Niels Bohr
Typology: Exercises
1 / 3
This page cannot be seen from the preview
Don't miss anything!
On special offer
J. J. Thompson (Late 1800s): J. J. Thompson was an English scientist. He discovered the electron when he was experimenting with gas discharge tubes. He noticed a movement in a tube. He called the movement cathode rays. The rays moved from the negative end of the tube to the positive end. He realized that the rays were made of negatively charged particles – electrons.
Lord Ernest Rutherford (1871 – 1937): Ernest Rutherford conducted a famous experiment called the gold foil experiment. He used a thin sheet of gold foil. He also used special equipment to shoot alpha particles (positively charged particles) at the gold foil. Most particles passed straight through the foil like the foil was not there. Some particles went straight back or were deflected (went in another direction) as if they had hit something. The experiment shows: Atoms are made of a small positive nucleus; positive nucleus repels (pushes away) positive alpha particles Atoms are mostly empty space
BECAUSE MOST PARTICLES PASSED STRAIGHT THROUGH THE FOIL LIKE THE FOIL WAS NOT THERE
MOST PARTICLES PASSED STRAIGHT AND SOME PARTICLES WENT STRAIGHT BACK OR WENT IN ANOTHER DIRECTION
BECAUSE THE NUCLEUS REPELLED THE ALPHA PARTICLES, AND PARTICLES REPEL WHEN THEY HAVE THE SAME CHARGE.
For more information https://www.youtube.com/watch?v=XBqHkraf8iE https://www.youtube.com/watch?v=IQ1h_gdVlHg https://www.youtube.com/watch?v=Pc0LWkUWPI