CHEM101 Lecture Notes - Lecture 1: Cathode Ray, Carbon Tetrachloride, Antoine Lavoisier

• School: University of Alberta
• Department: Chemistry
• Course: CHEM101
• Professor: bowen-forbes,camille

Document Summary

Chemistry is the study of matter, which can be classified as: elements (h, o, s, zn, etc, compounds (hcl, co2, sio2, nh3) substances, mixtures (saline, n2 and o2) substances. Elements the simplest type of substance with unique physical and chemical properties. An element consists of only one type of atom. Compound a substance composed of two or more elements that are chemically combined. Mixture a group of 2 or more elements and/or compounds that are physically intermingled. A physical mixture of the elements fe and s8 can be separated using a magnet vs. Fe and s have reacted chemically to form the compound fes. The elements cannot be separated by physical means. Mass law: law of conservation of mass (lavoisier 1789) In other words, the total mass of substances present does not change during a chemical reaction: law of defined proportions (proust 1799) A given compound always contains exactly the same proportion of elements by mass. (more precise by atoms)