To get the molecular formula you must either know the molecular mass or do an experiment to find it. This changes the percents to grams. 5 N 1401 a m u N 1703 a m u N H 3 100 8227 6 H 3024 a m u N 1703 a m u N H 3 100 1776 This same approach may be taken considering a pair of molecules a dozen molecules or a mole of molecules etc.
Percentages can be entered as decimals or percentages ie.
This is a worked example problem showing how to calculate mass percent composition. Created by Sal Khan. If youre seeing this message it means were having trouble loading external resources on our website. 31831 gmol 15906 gmol 2001 empirical units per molecular unit.