CHM 1311 Lecture Notes - Lecture 1: Atomic Number, Atomic Nucleus, Robert Andrews Millikan

• School: University of Ottawa
• Department: Chemistry
• Course: CHM 1311
• Professor: Kathy Focsaneanu

Document Summary

Composition: relative proportions of the components of a sample of matter (i. e. water is 11. 19% h & 88. 81% o by mass) Chemical property: observing a change in chemical composition. Mass: quantity of matter in an object. Weight: force of gravity on an object. Absolute zero: 0 k or -273. 15 c. Freezing point: 273. 15 k or 0 c. Boiling point: 373. 15 k or 100 c. Signi cant figures: digits that are considered signi cant in calculation & measurements. All non zero digits are signi cant (1. 432 g) But zeros between two signi cant gures are also signi cant (1. 032 g) Zeros to the left of a signi cant gure is not signi cant (0. 1432 g) If the value is < 1, then zeros to the right are signi cant (3. 00 g) When converting to scienti c notation, some zeros may be signi cant (4500 g can be 4. 5 x 10^3, 4. 50 x 10^ 3 or 4. 500 x 10 ^3)