The empirical formula of hydrocarbon is CH2
The molecular formula of the hydrocarbon is C6H12
Explanation
Hydrocarbon is made up of carbon and hydrogen
Step 1: find the moles CO2 and H2O
moles =mass/molar mass
moles of CO2 = 6.59 g/ 44 g/mol = 0.15 moles
moles of H2O = 2.70 g / 18 g/mol = 0.15 moles
Step 2: Find the moles ratio of Co2:H2O by diving each mole by smallest mole(0.15)
that is for CO2 = 0.15/0.15 =1
For H2O = 0.15/0.15 =1
therefore the mole ratio of Co2 : H2O = 1:1 which implies that 1 mole of Co2 and 1 mole of H2O is formed during combustion reaction.
From the the law of mass conservation the number of atoms in reactant side must be equal to number of atoms in product side
therefore since there 1 atom of C in product side there must be 1 atom of C in reactant side.
In addition there is 2 H atom in product side which should be the same in reactant side.
From information above the empirical formula is therefore = CH2
Molecular formula calculation
[CH2}n= 84 g/mol
[12+ (1x2)] n = 84 g/mol
14 n = 84 g/mol
n = 6
multiply the each subscript in CH2 by 6
Therefore the molecular formula = C6H12
