How to find the relative formula mass:
Add up the relative atomic masses together (times by the small number at the end if there is one)
Percentage mass of an element in a compound
Ar x number of atoms of that element
How to find the percentage mass of sodium carbonate Na2CO3
Find the Mr = 106
Percentage mass of sodium=43%
Describe the law of conservation of mass:
The law of conservation of mass says that no atoms can be created or destroyed in a chemical reaction. Therefore, the total mass of reactants must equal the total mass of products.
What is the Law of Conservation of mass?
Total mass of reactants=total mass of products
What is relative (molecular) mass?
Mr= sum of (Ar)