A 3.48 gram sample of sodium sulfate hydrate lost 1.35 gram of water when heated to constant weight. What is the formula of the hydrate?

this is what I did, but I am stuck.
Na2SO4 . H2O------> NA2SO4+H20

1 answer

So the mass of water is what? The loss due to water is the 1.35. How much is left?
3.48 - 1.35 = ?? must be the mass of the anhydrous Na2SO4.
So determine moles Na2SO4 and moles H2O. Convert those moles to small whole numbers just as if you had a percentage problem and want to know the empirical formula.