Chapter 2 - The Atom Flashcards
The scientific name for materials
Matter
What is diffusion
The spreading of gases from an area of high concentration to an area of low concentration
How did we come up with atom
The Greek work “atomos” meaning indivisible gave us the word atom.
What is Dalton’s Atomic Theory
- All matter is made up of very small particles called atoms
- All atoms are indivisible. They cannot be broken down into simpler particles.
What are cathode rays
Streams of negatively charged particles called electrons. They travel in straight lines from the cathode to the anode, are deflected by electric and magnetic fields, and have sufficient energy to move a small object such as a paddle wheel. They also cause glass to fluoresce
Who discovered electrons?
J.J Thomson
Who discovered the ratio of charge to mass of the electron was e/m?
J.J Thomson
Who measured the charge of an electron and calculated the mass of an electron
Robert Millikan
Who discovered the nucleus?
Ernest Rutherford
Who discovered the proton
Ernest Rutherford
Who discovered the Neutron
James Chadwick
What are the subatomic particles
Protons, neutrons and electrons
