Suggested End-of-Chapter Problems: All of them!  You should do as many problems as necessary in order to develop your mastery of the concepts. Pay particular attention to the later problems, as these are more relevant to test-level questions. Extra Practice on the website

Note: While reading this chapter, please keep in mind that there are 3 ways to report how much material one has: 1) in terms of the total mass of the sample, 2) in terms of the total number of unit particles contained in the sample, and 3) the number of moles contained in the sample. Each is just a different way of expressing an amount, with the mole being the SI unit for amount.

Objectives: 

6.2 & 6.3 & 6.4 & 6.5 

·        understand and define formula unit and formula mass

·         understand and define mole, Avogadro’s number

·         understand the relationship between 1 mole of any substance and the number of particles of that substance

·         convert between moles and numbers of atoms for an element

·         convert between moles and numbers of particles of a compound

·         convert between moles of a compound and moles of a constituent element for any substance

·         understand and define molar mass and determine the mass of 1 mole of any element or compound

·         convert between mass, number of moles, and number of particles for any substance

6.6 & 6.7 

·         understand and define percent composition (aka mass percent)

·         convert between grams of a compound and grams of a constituent element for any substance

·         solve composition problems using mass percents as conversion factors    

·         determine the percent composition of any material

6.8 & 6.9

·         understand and define molecular formula and empirical formula,

·         reduce a molecular formula to an empirical formula

·         calculate the empirical formula for a compound given its percent by mass of each element present or given the mass of each element

·         calculate the molecular formula for a substance given its empirical formula and molar mass (or formula mass)