Question

An organic compound contains 20% carbon, 6.7% hydrogen, and 46.67% nitrogen. Its molecular weight was found to be 60. Find the molecular formula of the compound.

• A. $C{H}_{2}N{O}_2$
• B. $C{H}_4{N}_{2}O$
• C. $C{H}_2{N}_2{O}_2$
• D. $C{H}_3{N}_{2}O$

Answer 1

The correct option is B $C{H}_4{N}_{2}O$


Empirical formula weight = 12 + 4 = 28 + 16 = 60
Molecular mass = 60 (given)
Therefore, the empirical formula mass is same as the molar mass.
Hence, the molecular formula is $C{H}_4{N}_{2}O$.