EMPIRICAL&MOLECULAR FORMULAS

EMPIRICAL FORMULAS are the simplest formula of a compound. 
- show only the simplest ratios, NOT the actual atoms.

MOLECULAR FORMULAS give the actual number of atoms.












Empirical Formulas:
- to determine the empirical formula, we need to know the ratio of each element.
- to determine the ratio fill in the table below for each problem.


**MEMORIZE (make sure you know this table by heart<3)

example: A sample of an unknown compound is found to contain 8.4 of 'C', 2.1g of 'H' and 5.6g of 'O'. Determine the empirical formula. 

Molecular Formulas: 

- if you know an empirical formula to find the molecular formula you need the molar mass.

example: The empirical formula for a substance is CH2O and its molar mass is 60.0g/mol. Determine the molecular formula.

this video is pretty long, but pretty much worth watching!

POSTED BY THE FABULOUS IVY GLORIA