A crystaline salt with molecular weight 120 having mg 20% sulphur 26.6% oxygen 53.3% calculate molecular formula empirical formula
Answers
Answered by
2
Answer:
The empirical formula of the anhydrous salt comes out to be MgSO_{4}. Empirical formula mass = 120.
Molecular mass = 120.
Hence, molecular formula = MgSO_{4}.
As crystalline salt on becoming anhydrous loses 51.2% by mass, this means 48.8 g of anhydrous salt contains H _{ 2 }O = 51.2 g. Therefore, 120 g of anhydrous salt contains
51.2 / 48.8 x 120 g = 126 g = 126/18 molecules = 7 H _{ 2 }O molecules
Hence, molecular formula of crystalline salt = MgSO_{4} • 7$H _{ 2 }O$
Similar questions