Calculating X in Hydrate Na2CO3 . XH2O Using Mass Loss Method

[awesome88]

hydrate problem :(

Homework Statement

When a hydrate of Na2CO3 . XH2O is heated until all of the water is removed, it loses 54.3 % of its mass. What is the value of X?

Homework Equations

The Attempt at a Solution

such a bad attempt...

Na2CO3=46g + 12g +48g=106g/mol
H2O=18g/mol

106+18=124 x 0.543=67.33g

I have no idea how to do this can someone please help me out

 

[chemisttree]

If 54.3% was water weight, that leaves 45.7% as the anhydride. This is like saying that for each 100 grams of hydrate dried, 54.3 grams was water and 45.7 grams was the anhydride. Can you take it from there?

 

[symbolipoint]

If 54.3% was water weight, that leaves 45.7% as the anhydride. This is like saying that for each 100 grams of hydrate dried, 54.3 grams was water and 45.7 grams was the anhydride. Can you take it from there?

The next step could be to find the number of moles of Na2CO3 and the number of moles of water; and then directly find mole ratio.