CHEM 1610 Chapter Notes - Chapter 3: Unified Atomic Mass Unit, Stoichiometry

• School: Ohio State University
• Department: Chemistry
• Course: CHEM 1610
• Professor: All

Document Summary

The mole once we know the mass of a sample we can calculate mass of the atoms or molecules in the sample to determine how many atoms/molecules are in the sample. Example (using amu): 1. 00kg 12c(1000g/kg)(1 amu/1. 660551x10-24)(12c atom/12. 00 amu) = Example (using moles): 1. 00 kg 12c(1000g/kg)(mole 12c/12. 00g 12c) = 83. 3 moles 12c. Mass percent of a component = (mass of component/total mass of sample) x 100. Ex: what is mass percent of c, h, o in ethanol, c2h6o. Mass % c = (24. 022/46. 069) x 100 = 52. 15% Combustion analysis: when chemist make new compounds they first determine % of each element, combustion device is used for c, h analysis, h20 and co2 are produced during combustion. 40. 69% c, 45% h, so 100-40. 69-45= 54. 6% 0.