1. Determine the Molar mass of the following compounds

 a. P₂O₃

b. BaSO₄

c. Mg(C₂H₃O₂)₂   

d. lithium carbonate

2. Calculate the Percent Composition of oxygen in the following compounds

a.       SO₃ 

b. CH₃COOH

c. Ca(NO₃)₂

d. Ammonium Sulfate

3. Calculate the empirical formula for the following compounds from percent composition

a.       0.0130 mol C, 0.0390 mol H, 0.0065 mol O

b.      11.66 g iron, 5.01 g oxygen

c.       40.0 percent C, 6.7 percent H, and 53.3 percent O by mass

4. Calculate the empirical formula for the following

a.       15.8% carbon and 84.2% sulfur

b.      43.6% phosphorus and 56.4% oxygen

c.       28.7% K, 1.5% H, 22.8% P and 47.0% O

5. Calculate the molecular formula for the following

a.       empirical formula CH, molar mass = 78 g/mol

b.      empirical formula NO₂, molar mass = 92.02 g/mol

c.       caffeine, 49.5% C, 5.15% H, 28.9% N, 16.5% O by mass, molar mass = 195 g.

Answers.

1. a. 109.05 g/mol  

b. 233.29 g/mol

c. 142.39 g/mol

d. 73.89 g/mol