CHEM 101 Lecture Notes - Lecture 1: Atomic Number, Mass Number

• School: Texas A&M University
• Department: Chemistry
• Course: CHEM 101
• Professor: Williamson Vickie

Document Summary

The idea of atoms was ignored for more than 2000 years. Dalton"s theory- all matter is composed of atoms. Atoms of the same element are exactly alike. The same compounds have the same number and type of atoms. This overturned dalton"s idea that atoms were indivisible. Thomson proposed the blueberry muffin/ plum pudding model of atoms. The charge of an electron is -1. 6 x 10^-19. Rutherford proposed that the nucleus was positive and surrounded by electrons. James chadwick discovered that atoms had neutral particles. Isotopes have the same number of protons but a different amount of neutrons.