CHEM 1131 Chapter Notes - Chapter 3: Molar Mass, Ammonium Chloride, Molecular Mass
Document Summary
Chem 1131 chapter 3: stoichiometry: ratios of combination. Using atomic masses from the periodic table and a molecular formula, we can determine the molecular mass. Molecular mass mass in atomic mass units (amu) of an individual molecule. Sum of the atomic masses of the atoms that make up the molecule. Ex: molecular mass of h20 = 2(atomic mass of h) + atomic mass of o. Formula mass mass of an ionic compound determined by the empirical formula. Ex: find the formula mass of sodium chloride. Ba(ch3coo)2 = 137. 33 + 4(12. 01) + 6(1. 008) + 4(16. 00) From a molecular or empirical formula, we can calculate what percent of the total mass is contributed by each element in a compound. Percent composition by mass list of the percent by mass of each element in a compound. Calculated by dividing the mass of each element in a unit of the compound by the molecular/formular mass.
