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Chemistry Homework – Molecular Formulas
Name
1. Calculate the molecular formula of the compound whose molar mass is 60.0 g/mol and empirical formula
is CH4N.
2. Find the molecular formula of each compound given its empirical formula and molar mass.
a. Ethylene glycol (CH3O), used in antifreeze, molar mass = 62 g/mol
b. p-dichlorobenzene (C3H2Cl), mothballs, molar mass= 147 g/mol
3. Which pair of molecules has the same empirical formula?
a. C2H4O2 , C6H12O6
b. NaCrO4 , Na2Cr2O7
4. The compound methyl butanoate smells like apples. Its percent composition is 58.8% C, 9.8% H, and
31.4% O. Methyl butanoate’s molar mass is 102 g/mol. What is its molecular formula?
5. Which of the following molecular formulas are also empirical formulas? (Circle all that apply)
a. Ribose (C5H10O5)
b. Ethyl butyrate (C6H12O2)
c. DEET (C12H17ON)
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Chemistry Homework – Molecular Formulas
Name
6. Determine the molecular formula for each compound
a. 94.1% O and 5.9% H; molar mass= 34 g
b. 40.0% C, 6.6% H, and 53.4% O; molar mass= 120 g