CHE 131 Chapter Notes - Chapter 7: Unified Atomic Mass Unit, Barium Chloride, Calcium Fluoride

• School: Stony Brook University
• Department: Chemistry
• Course: CHE 131
• Professor: Benjamin Hsiao; Jiangyong Jia; Roy Lacey

Document Summary

Molecular mass (formula mass) is the average mass of molecules (formula unit) in atomic mass unit. molecular mass = sum of atomic masses in molecule formula mass = sum of atomic masses in formula unit. Molecular mass of co2 = atomic mass of carbon. = 12. 01 amu + 2 x 16. 01 amu = 44. 01 amu. Mole is the si unit for amount of substance. One mole of substance is the amount of substance that contains as many elementary entities(atoms, molecules, ions ) are there are atoms in exactly 12 grams of carbon-12. One mole of any substance contains the same number of units as the number of atoms in exactly 12 grams of carbon-12. 1 mole of any substance = 6. 02 x 10 23 units of that substance. The number of objects per mole is called avogadro constant, n = 6. 02 x 1023 units per mole. The avogadro constant is a conversion factor between units and mole.