Draw a resonance structure for the cyclopentadienyl anion. be sure to show all non-bonding electrons and charges explicitly.

The resonance structure for the cyclopentadienyl anion is shown in the drawing below.

Explanation:

The resonance representation of the cyclopentadienyl anion shows that it is a stable ion. On the other hand it is important to note that it has 6 π electrons and is aromatic.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.