Question

Give an example where two compounds have same molecular as well as empirical formula mass.

Answer 1

1. Carbon Dioxide (CO₂) and Propane (C₃H₈)

i. Carbon Dioxide (CO₂):

Empirical Formula = CO₂

Molecular Formula = CO₂

Mass = 12 + (2 × 16)

= 12 + 32

= 44 g/mol

ii. Propane (C₃H₈):

Empirical Formula = C₃H₈

Molecular Formula = C₃H₈

Mass = (3 × 12) + (8 × 1)

= 36 + 8

= 44 g/mol

2. Nitrous Oxide (N₂O) and Acetaldehyde (C₂H₄O):

i. Nitrous Oxide (N₂O):

Empirical Formula = N₂O

Molecular Formula = N₂O

Mass = (2 × 14) + 16

= 28 + 16

= 44 g/mol

ii. Acetaldehyde (C₂H₄O):

Empirical Formula = C₂H₄O

Molecular Formula = C₂H₄O

Mass = (2 × 12) + (4 × 1) + 16

= 44 g/mol