what is the Lewis structure for HONO2(HNO3)

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what is the Lewis structure for HONO2(HNO3)?

The correct answer and explanation is :

The Lewis structure for HNO₃ (Nitric Acid), which is often written as HONO₂, consists of hydrogen (H), nitrogen (N), oxygen (O), and the following bonding arrangement:

Lewis Structure for HNO₃ (Nitric Acid):

  1. Atoms involved:
  • Hydrogen (H)
  • Nitrogen (N)
  • Oxygen (O)
  1. Structure:
  • Nitrogen (N) is the central atom, surrounded by three oxygen atoms.
  • One of the oxygen atoms is bonded to the nitrogen with a double bond (N=O).
  • The other two oxygen atoms are bonded to nitrogen with single bonds, one of which also carries a hydrogen atom (forming a hydroxyl group, -OH) and the other carries a negative charge (this oxygen is part of a resonance structure).
  • The oxygen that is bonded to nitrogen with a single bond and has a negative charge is typically shown as having two lone pairs of electrons. This oxygen is involved in resonance with the other oxygen atoms, spreading the negative charge.
  • There is also a formal positive charge on the nitrogen atom.
  1. Formal Charges:
  • Nitrogen has a formal charge of +1.
  • The oxygen attached to nitrogen with a single bond and the hydroxyl group (-OH) has no formal charge.
  • The oxygen that carries a negative charge has a formal charge of -1.
  • The oxygen double-bonded to nitrogen has no formal charge.
  1. Electron Distribution:
  • The nitrogen atom shares electrons with the oxygen atoms to form bonds, while also maintaining lone pairs to satisfy the octet rule.
  • Oxygen atoms generally follow the octet rule, except for the oxygen with a negative charge (which holds three lone pairs).

Resonance:

  • Nitric acid exhibits resonance, which means the actual structure is a hybrid of several possible Lewis structures. The negative charge on the oxygen atom can shift between the single-bonded oxygen atoms, leading to various resonance structures.

Summary of Bonds:

  • One N=O (double bond)
  • One N-OH (single bond)
  • One N-O⁻ (single bond with formal negative charge)

Important Concepts:

  1. Octet Rule: Nitrogen and oxygen follow the octet rule, sharing electrons to complete their valence shells.
  2. Resonance: The structure of HNO₃ is best represented as a resonance hybrid, as the electron distribution is delocalized over the three oxygen atoms.
  3. Formal Charge: The formal charges ensure the molecule is electrically neutral. The nitrogen atom has a formal positive charge, and one oxygen atom carries a negative charge.

This structure describes nitric acid (HNO₃), often referred to as HONO₂ in certain contexts, with the hydrogen atom bonded to one of the oxygen atoms.

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