IB Chemistry HL 1.4.4 Empirical & molecular formulas
IB Chemistry HL 1.4.4 Empirical & molecular formulas
Derive empirical and molecular formulae from combustion masses, percentage data or Mr, and reduce mole ratios to the simplest whole numbers.
How this is tested
- find an empirical formula from CO2 and H2O data, then use remaining mass to get oxygen
- use empirical formula mass and Mr to deduce molecular formula, e.g. P2O3 -> P4O6
- distinguish molecular and empirical formulae for compounds like phenolphthalein, C20H14O4