10.3 Percent Composition and Empirical Formula

Fertilizer

Percent Composition is the percent mass of each element in a compound. % composition of a compound is always the same % mass of element = mass of element in 1 mol compound x 100% molar mass of compound

Practice Solve: What is the percent composition of propane? C3H8? You’re gearing up for the Superbowl and have decided to grill some Franks using your propane grill. Equation: % comp = mass element in 1 mol x 100% molar mass compound Solve: What is the percent composition of propane? C3H8?

Calculate the % composition of these compounds Ethane (C2H6) 2. Sodium hydrogen sulfate ( NaHSO4)

Calculate the % Nitrogen in these fertilizers 3. NH3 4. NH4NO3

Empirical and Molecular Formulas Empirical formula: gives the lowest whole-number ratio of atoms of the elements in a compound. The molecular formula tells the actual # of each kind of atom present in the molecule. Hydrogen Perioxide: H2O2 HO H2O2 Empirical Formula Molecular Formula Chemical Formula http://www.brightstorm.com/science/chemistry/chemical-reactions/empirical-formula-molecular-formula/

Which of the following compounds have the same empirical formula? A. CO2 and SO4 B. C7H14 and C10H20 C. C4H10 and C10H4 D. C6H12 and C6H14

The lowest whole-number ratio of elements in a compound is called the A. empirical formula B. molecular formula C. binary formula D. representative formula

What is the percent by mass of Carbon in acetone, C3H6O? A. 20.7% B. 62.1% C. 1.61% D. 30.0%

What is the percent by mass of chromium in BaCrO4? D. 25.2%