What is the formula of the hydrate when 6.584g of one of the hydrates of sodium sulfate (Na2SO4) was heated?

Question

When 6.584g of one of the hydrates of sodium sulfate (Na2SO4) was heated to drive off all of its water of hydration, the residue of anhydrous sodium sulfate had a mass of 2.889g. What is the formula of the hydrate?

Answer 1

dude, awesome question! no one knows though, good luck!  

Answer 2

I have no clue but I bet it tastes like c**p.

Answer 3

wooah!!!i have no idea what you just said!!!!