Calculate the relative formula mass (Mr) of BaCO3
So relative formula mass (Mr) just means the total mass of all the atoms within our molecule. So lets work out how many of each atom we have: Ba - 1, C - 1, O - 3Now we know the relative atomic mass of each of these (Ba - 137, C - 12, O - 3, as provided)
So now we multiply the masses by the amount of each atom and then sum the totals to give us the total mass of the molecule: ((137 x 1) + (12 x 1) + (16 x 3)) = 197
