Question

The azide ion, n−3, is a symmetrical ion, all of whose contributing structures have formal charges. draw three important contributing structures for this ion.

Answer 1

The azide ion N3- can actually be represented by 3 resonance structures.

(check attached image for the structures)

 

Among the three, the Structure 1 is the most important one. While structure 3 almost makes no contribution due to the positive charges located on the adjacent atoms and the overall higher formal charge.

Answer 2

Azide ion has $\boxed{{\text{three}}}$ resonating structures (For structures, refer to the attached image).

Further Explanation:

The bonding between the different atoms in covalent molecules is shown by some diagrams known as the Lewis structures. These also show the presence of lone pairs in the molecule. These are also known as Lewis dot diagrams, electron dot diagrams, Lewis dot structures or Lewis dot formula. In covalent compounds, the geometry, polarity, and reactivity are predicted by these structures.

When more than one Lewis structures are possible for a single molecule but no single structure is able to explain all the properties of the molecule then resonance is used. All the structures thus formed are called resonating structures and the phenomenon is known as resonance. The resonance structures have the same placement of atoms but different locations of bond pairs and lone pairs of electrons. Moreover, various resonating structures can be converted to each other by moving lone pairs to bonding positions, and vice-versa.

The general rules that we follow to draw the resonance structures are as follows:

a. The $\pi$ electrons or a lone pair of electrons can change their positions while the position of atoms remains fixed.

b. The count of the valence electrons in all the resonating structure should be same.

c. The transfer of electrons is shown by the curved arrows.

d. The resonating structure must follow octet rule that is all atoms should have 8 electrons

Conditions to determine more contributing resonating structures are as follows:

1. Smaller formal charges are always preferred over the larger one.

2. The stable structure has more delocalization of charges on the atoms.

3. A more negative formal charge must always be located on the most electronegative atom.

The resonating structures of azide ion are shown in the image attached.

Structure III is more stable than the other two. This structure has negative charge on more electronegative atom (N) and more delocalization of charge. While in structure I and II, nitrogen is having a positive charge so unstable.

Learn more:

1. The moles of ${\text{NaOH}}$ : brainly.com/question/4283309

2. The correct name of the compound: brainly.com/question/9535482

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Resonance

Keywords: resonating structures, azide, N3-, structure I, structure II, structure III, Lewis structures, smaller, larger, electronegative atom.