Question

Which describes the correct number and types of atoms in this molecular structure?


1. five C, eight H, two O

2. three C, two O, six H

3. two C, two O, nine H

4. four C, eight H, two O

Answer 1

Answer: Option (1) is the correct answer.

Explanation:

The molecular structure is as follows.

           $CH_{3}-CO-CH_{2}-CO-CH_{3}$

This compound contains carbon (C) atoms, hydrogen (H) atoms, oxygen (O) atoms.

Or, the chemical formula of this compound is $C_{5}H_{8}O_{2}$.

Thus, we can conclude that there are five carbon atoms, eight hydrogen atoms and two oxygen atoms.  

Answer 2

Answer: Option (1) is the correct answer.

Explanation:

The given compound is a di-ketone as it contains two molecules of the functional group $C=O$.

So, in total there are two $CH_{3}$ and two $C=O$ groups but there is one $CH_{2}$ group.

Hence, we can conclude that in total the correct number and types of atoms in this molecular structure are as follows.

Carbon atoms = 5

Oxygen atoms = 2

Hydrogen atoms = 8