The Mr

• the Mr is the relative formula mass which is just the relative atomic masses Of all the atoms in the molecular formula added together
• How to find the Mr:

  1. Look up the relative atomic masses of all the elements in the compound on the periodic table
  2. Add up all the relative atomic masses of the atoms in a compound
• To calculate the % mass of an element in a compound

  Atomic mass x number of atoms of that element ÷ Mr of the compound X100