Question

A compound with the empirical formula CH2 has a molar mass of 126g/mol. What is the molecular formula for this compound?

Answer 1

Answer: C10H20

Explanation:

C=12

H=1

(12+1)n=126

13n=126

n=126/13

n=10

Molecular formula

C10H20

Answer 2

Answer:

The compound has a molecular formula of C9H18

Explanation:

Step 1: Data given

the compound has an empirical formula of CH2

The molar mass of the compound is 126 g/mol

Molar mass C = 12 g/mol

Molar mass H = 1 g/mol

Step 2: Calculate the molar mass of the empirical formula

We have 1x C and 2x H

Molar mass = 1*12 + 2*1 = 14 g/mol

Step 3: Calculate the molecular formula

126 / 14 = 9

We have to multiply the empirical formula by 9 to have the molecular formula

9*(CH2) = C9H18

The compound has a molecular formula of C9H18