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Measurements and Calculations in chemistry - Molecular formulas. Dr. Chin Chu Chemistry River Dell High School. Definition:. Molecular Formula - of a chemical compound identifies the number of each type of atom in a molecule. background. Examples. The process.
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Measurements and Calculations in chemistry- Molecular formulas Dr. Chin Chu Chemistry River Dell High School
Definition: Molecular Formula - of a chemical compound identifies the number of each type of atom in a molecule.
Molecular formula Examples • A compound was composed of carbon (85.7% by mass) and hydrogen (14.3% by mass) with a molecular weight (molar mass) of 64.0 g/mol. What is the molecular formula for this compound?
Molecular formula – exercise problems • A compound was analyzed to be composed of nitrogen and oxygen. Percent composition of each element is 30.4% (nitrogen) and 69.6% (oxygen). Molar mass of the compound was measured to be 92.0g/mol. What is the molecular formula for the compound? • What is the molecular formula for a compound consists of carbon(25.9% by mass) and hydrogen (74.1% by mass) and a molecular weight (molar mass) of 78.0g/mol.? • What is the molecular formula for a compound consists of carbon (32.7% by mass), hydrogen (2.0% by mass), and oxygen (65.3% by mass) with a molar mass (molecular weight) of 180.0 g/mol.?
Empirical formula – Answers • [N2O4] • [C6H6] • [C6H12O6]