What is the molecular formula of the compound with a molecular weight of 112 g/mol and percent composition: 85.6% c and 14.4 % h

The molecular formula is C8H16

Explanation:

Step 1: Data given

The molecular weight = 112 g/mol

The compoun contains 85.6 % C and 14.4 % H

Step 2: Calculate mass of C and H

Let's consider 100 gram of this compound

⇒ 85.6 % of C = 85.6 grams of C

⇒ 14.4 % of H = 14.4 grams of H

Step 3: Calculate moles of C

Moles C = Mass C / molar mass C

Moles C = 85.6 grams / 12.0 g/mol

Moles C = 7.13 mol

Step 4: Calculate moles of H

Moles H = 14.4 grams / 1.01 g/mol

Moles H = 14.3 moles

Step 5: Calculate the mol ratio

We divide by the smallest amount of moles

C: 7.13/7.13 = 1

H: 14.3 / 7.13 = 2

The empirical formula is CH2

The molar mass of the empirical formula is 14.02 g/mol

Step 6: Calculate the molecular formula

We have to multiply the empirical formua by n

n = 112 g/mol / 14.02 g/mol

n = 8

The molecular formula is C8H16