CHEM101 Lecture Notes - Lecture 2: Mass Spectrum

• School: University of Alberta
• Department: Chemistry
• Course: CHEM101
• Professor: Sai Yiu

Document Summary

Chem 101 - lecture #2 - atomic structure pt. Chemistry is closely related to our daily lives. Democritus (460 - 370 bc): matter was made up of indivisible particles - called atoms. Law of conservation of mass: matter is created nor destroyed. Law of constant composition: a given sample of compound always contains the same fraction of element by mass. Eg. calcium carbonate, where ca = 40%; c = 12%; o = 48% Law of multiple proportions: when two elements a and b form more than one compound, the masses of element a that combine with a fixed mass of b are in simple ratio. Co2 (carbon dioxide), where c = 27. 3% ; o = 72. 7% 1g of c that is, for 1g of c, the mass of o is 2. 66g. Co (carbon monoxide), where c = 42. 9% ; o = 57. 1% 1gof c that is, for 1g of c, the mass of o is 1. 33g.