CHEM 105aLg Lecture Notes - Lecture 1: Conversion Of Units Of Temperature, Chemical Change, Si Derived Unit

57 views8 pages
2 Dec 2016
School
Department

Document Summary

A law, which has no exceptions, summarizes what happens experimentally through observations. Theories attempt to explain observations and laws. A theory may not be totally correct but can still be useful. The scientific study of matter, its properties, and interactions with other matter and with energy. Chemistry comprises everything in the universe except for the space in a vacuum. It exists in three classical states (solid, liquid, gas) and many non-classical states exist (glass, plasma, liquid, crystal) Pure substances have constant compositions: elements cannot be decomposed chemically into simpler substances, compounds can be broken down into elements, mixtures are impure. Homogeneous mixtures, or solutions have visibly indistinguishable parts. For heterogeneous mixture you can visually see the components which can be separated. Amber - heterogeneous (can see air bubbles and mosquito. Chapter 1 section 4 physical vs. chemical changes. Physical change: a change in the form of a substance, but not its chemical composition.