CH 101 Lecture Notes - Lecture 1: Critical Mass, Limiting Reagent, Positron
Document Summary
Atoms combine with one another to form molecules (h2 or ch4). An element is a substance that consists of only one type of atom (na or o2), and a compound is a substance that contains more than one type of atom (nacl or h2o). Our discussion of chemistry will start at the atomic level. Draw and label a diagram of an atom: Size of atom (1 = 1x10-10m): h (0. 37 ), br (1. 14 ) Antoine lavosier (late 1700s) measured mass of many reactions and conluded that during a chemical reaction, the total mass does not change (law of conservation of. John dalton"s atomic theory (early 1800s) helped to explain the law of conservation of. Mass since atoms do not disappear during a chemical reaction; allows us to balance reactions. This theory and his use of symbols allowed scientists to begin to make a connection between microscopic atoms and macroscopic experiments.
