Mass ratio of C:His4:1⇒12:3
& C:Ois3:4⇒12:16
so massmolemoleratioC1211H333O1611
Empirical formula ⇒CH3O
as compound is saturated acyclic so molecular formula is C2H6O2.
C2H6O2+25O2(g)⟶2CO2(g)+3H2O(g)
2mole 5mole
so required moles of O2is ⇒5