What’s the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen if the molar mass is 110 g/mol

Empirical formula :

Molecular formula :

Explanation:

STEP 1: Calculate the moles of each species i.e C , H , O

Molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen means

Mass of Carbon = 65.5 gram

Mass of Hydrogen = 5.5 gram

Mass of oxygen =  29.0 gram

Moles of C:

Molar mass of C = 12.0 gram

Moles of C = 5.45

Moles of H:

Molar mass = 1.0 gram

Moles of H = 5.5 moles

Moles of O :

Molar mass of O = 16.00 gram

Moles of O = 1.81 moles

STEP2 : Calculate the simple ratio of C ,H,O by dividing with 1.81 (Because it is the minimum moles present)

Always divide by minimum number of moles

For C

= 3.00

For H

= 3.03

= 3.00 (round off the answer to nearest whole number)

For O

= 1.00

So we get the empirical formula:

STEP 3: Calculate the "n" value to obtain the molecular formula using:

Empirical mass =

= 3(mass of C)+3(mass of H)+ mass of O

= 3x12 + 3x1 + 16

= 55 grams

Molar mass = 110 g/mole

n = 2

STEP 4: Multiply the empirical formula with n