Question

Be sure to answer all parts. Pure HN3 (atom sequence HNNN) is explosive. In aqueous solution, it is a weak acid that yields the azide ion, N3−. Draw one resonance structure for N3− and one resonance structure for HN3. Include all lone pair electrons and nonzero formal charges in your structures.

Answer 1

Answer:HN3 is a weak acid as its conjugate base anion formed after deprotonation is very unstable.

Kindly refer the attachments for the resonating structures of HN3 and N3- anion.

Explanation:

Kindly refer the attachment for structure of azide ion.

The azide ion is a explosive due to the highly unstable structure of azide ion and a strong tendency for the formation of nitrogen  molecule which is stable.

So azides decompose very quickly to give nitrogen molecule which is very stable on account of triple bond.

The azide ion basically has 3 resonating forms .There are 3 Nitrogen atoms and the central nitrogen atom is positively  charged as it forms double bonds with each of the two nitogens.

Although there is some delocalization of charges  present on the three nitrogen atoms but the fact is that in the structure there are  charges present of different polarity  .So one of the nitrogen is positively charged and other two nitrogens are negatively charged. Due to this separation of charges of different polarity this unstability arises. It is nitrogen only which has to carry the postive as well as negative charge.

The resonance structure of HN₃ is also similar as in this structure also there is charge separation between positive and negative charges but here due to the presence of hydrogen one of the negative charge is neutralised and molecule is sightly neutralized as no nitrogen atom has to bear 2 negative charge as in the case of azide ion.

Kindly refer the attachments: