In: Chemistry
Combustion of a 0.525g sample of an unknown organic compound containing only C, H, and O yielded 1.113g CO2 and 0.1708g of H20. What is the emperical formula of the compound? If the molar mass of the compound is 166.13g/mol, what is the molecular formula?
Please show work!!!!
moles of CO2 = 1.113 / 44 = 0.0253
moles of C= 0.0253
mass of Carbon = 12 x 0.0253 = 0.3036 g
moles of H2O = 0.1708 / 18 = 0.00949
moles of H = 2 x 0.00949 = 0.01898
mass of hydroegen = 0.01898 g
Oxygen mass = 0.525 - (0.3036 + 0.01898 ) = 0.2024 g
moles of O = 0.2024 /16 = 0.0126
C O H
0.0253 0.0126 0.01898
2 1 1.5
4 2 2
C4O2H2 -----------------------> empirical formula
empirical formula mass = 48 + 32 + 2 = 82
n = molar mass / empirical formula mass
= 166.13/82
= 2 (nearly)
molecular formula = n x empirical formula
= C8H4O4