CHEM 1031 Lecture 2: 9/2 Atomic Theory, Laws, Atomic Structure

• School: Temple University
• Department: Chemistry
• Course: CHEM 1031
• Professor: Doberieiner

Document Summary

2. 1 early ideas in atomic theory: atomic theory through the nineteenth century, dalton"s atomic theory. The smallest unit of an element that can participate in a chemical change. Elements have only one kind of atom, the atomic mass identifies the element. A compound has multiple atoms melded together in ratio. This ratio remains the same in the compound. Atomic preservation during chemical processes: conservation of matter , law of definite proportions/law of constant composition. All samples of a pure sample contain the same elements in the same proportion by mass : these ratios are not unique to each compound, ie . compounds with the same ratio can have different structures amongst the atoms. Law of multiple proportions: when two elements react to form more than one compound, a fixed mass of one element will react with masses of other element in a ratio of small whole numbers.