Formulas of Compounds, Exams of Chemistry

Download Formulas of Compounds and more Exams Chemistry in PDF only on Docsity! Formulas of Compounds Molecular Formals Chapter 6 It is important to remember that the molecular formula is always an integer multiple of the empirical formula. Molecular formula = (empirical formula)n To obtain the molecular formula we must know the _____________________________. Example: A white powder is analyzed and found to have an empirical formula of P2O5. The compound has a molar mass of 283.88g What is the compounds molecular formula? 1st find molar mass of empirical formula! 2nd Remember: Molecular formula= n x empirical formula Find n! 3rd Molecular formula = (empirical formula)n Example with percent composition! A compound used as an additive for gasoline to help prevent engine knock show the following percentage composition: 71.65 % Cl 24.27% C 4.07% H The molar mass is known to be 98.96g. Determine the empirical formula and the molecular formula for this compound.