CHEM101 Lecture Notes - Lecture 1: Cathode Ray, Beta Particle, Alpha Particle

• School: University of Alberta
• Department: Chemistry
• Course: CHEM101
• Professor: Yoram Apelblat

Document Summary

Elements, compounds, and mixtures: an atomic overview. Chemistry is the study of matter, which can be classified as: elements (h, o, s, zn, etc. , compounds (hcl, co2, sio2, nh3, mixtures (saline, n2 and o2) Element - 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 two or more elements and/or compounds that are physically intermingled. Fe and s8 can be separated using a magnet. Fe and s have reacted chemically to form the compound fes. The elements cannot be separated by physical means. Mass laws: 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 definite proportions. A given compound always contains exactly the same proportion of elements by mass. (more precise by atoms)