Question
A compound on analysis, is found to have the following composition:
(i) Sodium = 14·31%, (ii) Sulphur = 9·97
(iii) Oxygen = 69·50% (iv) Hydrogen = 6·22%.
Calculate the molecular formula of the compound assuming that whole of hydrogen in the compound is present as water of crystallisation. Molecular weight of the compound is 322.
Solution
(i) To calculate the empirical formula of the compound:
(ii) To calculate the molecular formula of the compound.
Empirical formula mass of,
Molecular mass = 322 [given]
Hence,
Whole of the hydtogen is present in the form of water. Thus, 10 water molecules are present in the molecule.
So molecular formula of the compound is Na2SO410H2O.
(ii) To calculate the molecular formula of the compound.
Empirical formula mass of,
Molecular mass = 322 [given]
Hence,
Whole of the hydtogen is present in the form of water. Thus, 10 water molecules are present in the molecule.
So molecular formula of the compound is Na2SO410H2O.
