CH-1010 Chapter Notes - Chapter 2: Rutherfordium, Seaborgium, Molecular Mass

• School: Clemson University
• Department: Chemistry
• Course: CH-1010
• Professor: Mycia Cox

Document Summary

For over 2000 years the concept of an indestructible atom also meant an indivisible atom. Atoms are not indivisible and are made of even tinier subatomic particles: positively charged protons, negatively charged electrons, and particles with no electrical charge called neutrons. The first subatomic particle to be discovered (by joseph john. He set out to better understand how gases conduct electricity. In his research he used a device called a cathode-ray tube. Electrodes within the tube are attached to the poles of a high-voltage power supply. Cathode rays are invisible to the naked eye, but when the end of the tube opposite the cathode is coated with a phosphorescent material, a glowing spot appears where the beam hits the coating. Thomson discovered that cathode-ray beams can be deflected by magnetic and electric fields. Cathode rays were not rays of energy, but rather charged particles of matter. The directions of the deflections told him that their charges were negative.