Chapter 4.3, Problem 4.5P

Interpretation Introduction

Interpretation:

The positions of all double bonds in the given structure of caffeine are to be shown.

Concept introduction:

Covalent bonds are formed by sharing of electrons between atoms.

The valence electrons of Carbon are 4 electrons (requires 4 electrons to achieve octet).

The valence electrons of Oxygen are 6 electrons (requires 2 electrons to achieve octet).

The valence electrons of Hydrogen are 1 electron.

The sharing of one electron from two atoms constitutes a single bond between the two atoms.  The sharing of two electrons from two atoms constitutes a double bond between the two atoms