Answer:
The empirical formula is =
The Valproic acid formula is =
Explanation:
Mass of the produced water = 0.166 g
Molar mass of water = 18 g/mol
The moles of are calculated as 0.166 g /18 g/mol = 0.00922 moles.
In 1 mole of water, there are 2 moles of hydrogen atoms.
Thus,
Moles of H = 2 x 0.00922 = 0.01844 moles
Each hydrogen atom's molar mass is 1.008 g/mol.
Hydrogen mass in the molecule = 0.01844 x 1.008 = 0.018588 g
Mass of produced carbon dioxide = 0.403 g
Molar mass of carbon dioxide = 44.01 g/mol
The moles of are calculated as 0.403 g /44.01 g/mol = 0.009157 moles.
Each carbon atom's presence is 1 mole in 1 mole of carbon dioxide.
So,
Moles of C = 0.009157 moles
The molar mass of carbon is 12.0107 g/mol.
Carbon mass in molecule = 0.009157 x 12.0107 = 0.11 g
Since Valproic acid comprises only hydrogen, oxygen, and carbon, the oxygen mass in the sample = Total mass - Carbon mass - Hydrogen mass.
The sample's overall mass = 0.165 g.
Oxygen mass in the sample = 0.165 - 0.11 - 0.018588 = 0.036412 g
The molar mass of oxygen is 15.999 g/mol.
Moles of O = 0.036412 / 15.999 = 0.002276 moles
Taking the simplest ratio for H, O, and C yields:
0.01844: 0.002276: 0.009157
= 8: 1: 4
The empirical formula becomes
While molecular formulas detail the precise count of atoms for each element, empirical formulas represent the simplest form or reduced ratio of these elements in the compound.
Consequently,
The molecular mass equals n × Empirical mass.
Here, n is a positive integer from 1, 2, 3...
Empirical mass = 4×12 + 8×1 + 16 = 72 g/mol.
Molar mass = 144 g/mol.
Thus,
The molecular mass = n × Empirical mass.
144 = n × 72
⇒ n = 2
The Valproic acid formula is =