An 8.442 g sample of Na2SO4 * xH2O is heated until all the water of hydration is driven off. The resulting anhydrous compound, Na2SO4 weighs 3.723 g. What is the formula of the hydrate?
Please explain to me how to do it too so I don't fail the text >.<
Please explain to me how to do it too so I don't fail the text >.<
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You lost 8.442-3.723g = 4.719 g water in the process
Or In mols (molecular weight H2O = 18.01 g/mol) 4.719/18.01 mol = 0.262 mol
Molecular weight Na2SO4: 142.04 g/mol. Therefore 3.723g Na2SO4 are 3.723/142.04 mol = 0.0262 mol.
That means since 0.262/0.0262 = 10 your molecular formula is Na2SO4 * 10 H2O.
Or In mols (molecular weight H2O = 18.01 g/mol) 4.719/18.01 mol = 0.262 mol
Molecular weight Na2SO4: 142.04 g/mol. Therefore 3.723g Na2SO4 are 3.723/142.04 mol = 0.0262 mol.
That means since 0.262/0.0262 = 10 your molecular formula is Na2SO4 * 10 H2O.