1. In a laboratory experiment, an undergraduate student collected a sample of ammonium phosphate. If the sample contains 9.52 x 10 25 molecules, how many grams of the sample did he
collected?

2. Determine the % composition for each element in Al 2 (SO 4 ) 3 ?

3. You have a 136.28 g sample of Beryllium Fluoride what is the mass of
a. Beryllium in the sample:

4. Find the empirical formula of a compound containing 3.160 g of Aluminum, 4.850 g of sulfur
and 8.680 g of oxygen?

5. Find the molecular formula if the empirical formula is C 2 H 3 O 2 and the molar mass is 105.1
g/mol.